Slow Week

This week has been even slower than the last, and I don't really have any cool fossil discoveries to report in on. Despite the fairly regular rains we've been getting lately (sometime between noon and 3:00 each day it's almost guaranteed to start pouring) there just hasn't been much new and interesting material exposed. There's no doubt that the water's been helping clear out sediment for us -- it's pretty common now to arrive at a site to find our quarries full of loose debris and it's obvious that there's a lot of movement going on on the hill slopes. We've been doing more prospecting than we have in the past in hopes of finding exposed fossils away from our usual hotspots, but all we've found are bits of turtle carapace and unidentifiable bone fragments. And while it's true that the quarries have produced more fossil material than in past visits, this material has also happened to be mostly unidentifiable bits or non-diagnostic remains (limb bones with no ends, simple fish teeth, etc.). There have been a few interesting finds, like a small, worn section of camel jaw, but they're greatly overshadowed by the amount of junk we've been pulling from the outcrops. The upside to it all is that the weather during our field work window (from 7:00 until whenever the sky threatens to rain down on us) has been phenomenal. The increase in cloud cover has noticeably upped the humidity, but that's more than compensated for by the steady winds and occasional drizzles that have also started up. So even though we're finding little and less, at least we're comfortable.

With all the disappointment in the field, my week has been much more about soccer than about paleontology. I've had a ton of opportunities to play, with work games on Fridays, pickup on Wednesdays, and a park less than a block from my apartment. I'm at the point where I play in one form or another every day and still find myself wanting more. My team's prospects for the work tournament aren't looking great at this point, but who knows, maybe we'll turn it around in the second half of the season. I think that the final games are on the Friday right before I leave for home, so the timing is pretty perfect.

This week has been relatively slow -- there are still permit issues, and Jorge has had a number of meetings/conference calls, so we haven't been spending a ton of time in the field. Still, we've managed to do a bit of field work and have ended up having a pretty varied week, which I'm all for since it helps the time pass a little faster.

Mangoes from Corozal.

On Monday we went to the off-site fossil storage building in Corozal to do more sediment screen washing. This is something I've done before and basically just involves playing with mud for a few hours, so I was excited from the moment I learned we'd be going. For the past few weeks we've had bags full of rocks sitting around in the lab prep room that we brought back with us from Hodges Microsite (Cucaracha Formation, ~20 million years old) and Jorge decided it was well time we took care of them. It was a perfect day for doing it too:  bright and sunny, which would have meant hell working on the canal, but on the shaded patio of our storage building with regular spray from the hose we used and a fully air-conditioned building at our disposal, we couldn't have been more comfortable.

The screening process itself.

Of the two steps involved in screen washing, the first is by far the easier and more enjoyable. You just empty your bag of rocks into a pail, cover with water and add a scoop of detergent, and start mixing with your hands. Most of the rocks (which, from Hodges, were all sandstones) go to mush on their own or with the slightest squeeze, so the job basically boils down to going after the few resistant rocks in the group while creating a slurry out of the whole so that it will (hopefully) go through the screens easily. Really, it's like hanging out chatting with your coworkers, while you just so happen to be elbow-deep in mud. The second step, though, is where things can get frustrating. There are three layers of screens, stacked on top of one another from finest at the bottom to coarsest at the top. Just about everything passes through the coarse screen, but in layer two things tend to get clogged up and can start overflowing. It takes a lot of patience with the hose running constantly and your hands trying to push the fine grains through; for the first few minutes it almost always feels like nothing is happening at all, but once things get going it's down hill from there. The screening process takes a while, but it's all worth it because only one person can do it at a time! So when it wasn't my turn on the screens at I was free to do whatever I wanted, and it just so happened that the yard behind our building was covered in mango trees with PLENTY of ripe mangoes! While one of us worked, the rest went around from tree to tree inspecting the fruit that had fallen to the ground and boosting each other up to reach the yellow/orange/red mangoes still attached to the branches. By the end of the day we had washed six bags of sediment and collected a few dozen mangoes -- a highly successful Monday!

On Tuesday we returned to Pina, with the intent to do more exploring and prospecting than we had been in the past few visits. Somehow we ended up walking a completely new section of beach, which amazed me, considering how many times we've been there by now. And there was plenty to find on this new stretch! Right off the bat Sam spotted a thumbnail-sized shark tooth ripe for the collecting, and things just got better from there. I found this one particular sandy bank that had a rib bone, a vertebra, a piece of turtle carapace, and more shark teeth than I ever would have believed! Granted, they were cookiecutter shark teeth, each no larger accross than a pencil eraser, but the sheer quantity more than made up for how small they were. They were quite literally falling out of the sandstone to the point that i couldn't look at any given spot without seeing one or rest my hand without setting one loose. It was really cool, and yet another reason to make me love Pina! I also learned that day that sea slugs are really bad at dealing with low tide -- I found two stranded on the beach and quickly heating/drying and another that was in less than an inch of water and struggling to follow the water out. Of course, I couldn't help but to put them into some safe tidepools, but for the two that were already starting to dry out I think survival chances were pretty slim. The one that was still in the water when I found it inked at me when I picked him up, which I had no clue slugs could do, so I think he ended up just fine.

Small rib I found on the beach.

Some kind of billfish skull -- we'll be
coming back for it!

Thursday marked our return to the canal zone, and it should be permanent this time! It's too bad that "permanent" will only last for three weeks until we go home (so soon!), but what can you do. Neither Thursday or Friday were particularly exciting as far as discoveries go, although I think Nicole found a complete molar at one of the sites. There's been a fair amount of rain since we last worked near the canal, so we're hopeful that as we tour the different localities we'll happen upon some newly-exposed major discoveries.

Success at Pina

Jacketed and ready to go!

We FINALLY recovered the skull from Pina up on the Caribbean side! It's really been an ongoing saga -- I remember first finding that thing all the way back in January. You may remember (but probably don't) that we were supposed to take the thing out last Friday. Well, we got up early that day and marched over to the labs as planned, only to find that our truck had been taken in for maintenance and that the only other available truck was so far on it's last leg that we were forbidden to even try taking it to the other side of the country and loading a huge rock into it. (You may also remember that one of our trucks, which happens to be the only other good one, broke down when we were coming back from the Azuero Peninsula.) From that Friday until today, every low tide was forecast for the early morning -- as in, pre-dawn early. So, when we finally made our way to Pina today (we still had to get up at 5:00...) we had our doubts about how solid the plaster jacket on the fossil would be. Or if it would even still be there at all. We were pleasantly surprised, then, when we found the thing in near-perfect condition. The plaster was just barely on the soft side in the very center (where it had been receiving the most sea-spray), but otherwise it was as if we had just made it earlier that day.

Without delay we set to popping the rock out of the cliff face. Since we had already created a nice, deep well in the previous visits, it was just a matter of putting a few chisels around the perimeter and driving them in towards the center to fracture the last remaining connection between our boulder and the wall it had once been a part of. Two people did the chiseling while another two held a homemade tarp-stretcher underneath to help break the fall onto the hard tidal flat. Despite feeling a little crowded with all of us standing on one another's feet, it actually worked pretty well. The boulder popped out with only a few well-placed chisels and we were more-or-less able to catch it with the tarp. The thing weighed a few hundred pounds, so we had no delusions about preventing it from hitting the ground entirely and were mostly just aiming for reducing the impact, which we were able to do. The only problem (something always to worry about when removing a fossil from a cliff face rather than from flat ground) was that some of the material extended even deeper into the wall than the trench we had carved out, so we had broken the fossil. Even worse, some of our chisel strokes had caused an additional fracture maybe half an inch behind the one that separated the boulder from the cliff, leaving a sheet of fossil + rock quite ready to pop off, which would almost certainly result in further breaks. We ended up carefully removing what bone fragments we safely could and left the rest for whoever might choose to study the skull and describe it. (It was nearly impossible to tell the orientation of the skull, so we were basically in there blind and decided there was too much risk to try extracting anything else.

The enamel is the little part pointing towards my wrist,
and the rest is all root.

Our imperfect extraction actually ended up helping us identify the specimen, since a tooth was left exposed after the boulder detached from the wall. This tooth was relatively small but had an extremely large root, something characteristic of a sperm whale. It's all about small victories sometimes. And although the day wasn't a perfect success, any time spent in beautiful Pina is time well spent and I thought we did pretty well with the skull, all things considered.

Bonus: sea slug hanging out in the shallows.

Soccer Season!

I may have already mentioned this a few posts back, but in case I skipped over it: volleyball season is over. My team (CTPA-Ancon) ended up 4th overall (basically right in the middle) with one of our players getting the tournament MVP, so it definitely could have gone worse. Although I've been enjoying playing more than I ever would have thought, I consider the end of the season to be good news because it means that soccer season is here! In fact, games started last Friday, so I'm a bit late in delivering the news. Up until now, I've only been able to play a small handful of times after work and I've mostly just been practicing on my own at the park at the end of the street, so I'm stoked that I now have a place to play regularly. We play on the same blacktop parking lot as the volleyball games (which is frightening) with five to a side, including goalies (why anyone would want to play goalie on cement is beyond me). My team only has seven players, which means that I get a lot of play time -- something I know I should be thankful for when I look at the teams with at least a dozen people. There are A LOT of really good players throughout all the teams, so I totally feel in over my head, but I've always felt playing with people better than you is a great way to practice. Plus, I held my own in our first game so I know I can keep pace when it comes down to it. I don't know how good our prospects are for the tournament (we lost our first match 0-1), but I'm just excited to be playing at all. It's been too long!

Pacific-side locks

Tuesday and Wednesday of this week were spent in a new area (for me) of the canal expansion zone, where the new locks to the Pacific are currently being constructed. We were given a very short-term and site-specific permit to work in this spot, but our requests for a long-term, general permit are still unanswered. I'm 99% sure this has to do with the fact that at our usual localities the work we do is STRI- and University of Florida-specific, while at this new Pacific locks site our work will directly benefit the canal authority. We essentially did the work of the ACP geologists for them -- they had passed the site off to us because they had found a few fossiliferous beds, so why not let us just do all of the measuring and describing and hand over our data once we'd finished. We want to do whatever it takes to maintain good relations with ACP, so we take care of the occasional odd jobs they throw our way, but three months of dealing with their selective communication and permit-withholding is really starting to wear on me. I can only imagine how frustrating it must be for the long-term employees like Aaron and Jorge.

The highly productive layers were where you can easily
see the slanting of the bed. Also, the mud made getting
to and from the outcrop quite a challenge!

I really shouldn't complain, though, since it gave me a chance to go to the field -- in all likelihood those chances will be few and far between from now until the end of the internship. And the work wasn't too demanding or challenging, just a bit on the dull side. Sam and Jorge measured the section, which wasn't much thicker than 25 meters, while Pedro, Nicole, and I prospected in the invertebrate-rich beds. On Tuesday I felt like a kid in a candy store; no collecting had ever been done at this site, so the best layers were just overflowing with easily-removed, well-preserved surface fossils. In the few hours I spent collecting there was hardly a continuous minute spent searching, since I was able to just go from one fossil to the next to the next. I even found a fragmented fish tooth, which was something we had really been hoping, but not expecting, to find. (I should say that not ten seconds after my find, Nicole found one that was both larger and more complete; I swear, the fossil gods must frown upon me!) Even being highly selective I was able to fill up two sample bags worth of inverts, no problem. The usual post-fieldwork ice cream bar at the nearby MiniSuper felt particularly well earned that day.

Scallop.

Wednesday was a group-wide prospecting day. Nicole and I worked mostly in one particular layer that had been highly productive the day before, while Pedro, Sam, and Jorge wandered around a bit more looking for anything new. It's a good thing they did because Pedro found a sizable (maybe 10 cm across) piece of turtle carapace that led to the discovery of even more turtle remains in the same bed. By the time the afternoon rolled around, all of us were digging bits of turtle out of that layer. They weren't the prettiest fossils I've ever seen (they were pretty heavily weathered and fragile, so they went to pieces when removed from the rock, even when prepared with glue) but they were pretty abundant so I'm sure we ended up with some good ones somewhere in there. Having explored the entire area and not having any particular interest in the kinds of things we found there, we bid the site farewell in the mid-afternoon and decided not to return for the rest of the week (the duration of our permit).

I should say a bit about the work site, since it was actually pretty cool. We don't usually work so far south when we're in the canal expansion area, so I had never seen that part of the expansion project before. Things are a lot further along there than they are in our usual spots -- instead of just demolishing and clearing and moving rubble around, they've already entered well into the phase of constructing the actual lock system. Security was extra tight so we had to be escorted each day by a safety and a security personnel  This, combined with the much heavier traffic of huge construction vehicles, really drove home just how expansive and complicated the expansion is. It felt much more like an active and frenzied construction zone than the comparatively deserted areas where we normally work. As we drove in both days, we would be adjacent and roughly at-level with the existing canal and would then descend down some 150 meters into the completely dry bottom of the soon-to-be expanded canal, a bizarre experience to say the least. And down in the bottom were the beginnings of the lock support structures -- imposing cement columns that shot straight up out of the pit. Together they formed what looked like a kind of gauntlet  almost like castle walls from which would-be attackers would be showered with arrows and hot oil. It was definitely a cool back drop to be working under.

Lab Work

Bin full of samples to-be-entered.

What, you may ask, have I been doing with all the time we've been spending in lab lately? The most time consuming task has been database entry. Everything that we collect for STRI, whether form the canal, from Pina, or from our field trip to Azuero, eventually needs to be cataloged and put into STRI's online database. It's incredibly straightforward work, but time-consuming nonetheless because there are so many different fields of information that need to be provided. What keeps me from losing my mind while entering in our hundreds and hundreds of samples is the section that requires me to list the taxonomic and morphological information of each fossil. When we're out in the field, we write general notes on the collection bags to indicate what kind of bone or tooth or whatever we've found and also what animal it came from. In the database I have to be more formal and specific, which has led me to learn a lot about the scientific names for various organisms (i.e. Turtles are from the order Testudines) as well as learn a bit about skeletal morphology (this is much more limited because Jorge usually takes care of it). It's been pretty fun and rewarding to actually get a bit of a handle on all the Latin words that I've heard thrown around since I got here.

My other main project in the labs has been general prep work. I finally finished cleaning up the fish vertebra that's been sitting on my desk for months, I've pieced together a few broken turtle bones, and cleaned up some inverts. Most of the bigger and more interesting projects get handed over to Nicole, who has more patience and care in one finger than I have in my entire person. I'm fine with it -- anything too big/important and I'll stress myself out about it to no end.

More Caribbean Breezes

It never gets old!

Once again back in my favorite field site: Playa Pina! Since we no longer have regular access to our canal localities, Pina is one of the few spots left to us where we can hope to do any relevant field work. Plus, Jorge specializes in fossil marine mammals (dolphins, whales, manatees , of which there are plenty to find, so he has a more positive attitude towards the place than Aaron ever did. As far as I'm concerned, the more trips to the Caribbean side, the better!

We took off for Pina around 10:00 AM, a bit later in the morning than usual since low tide was forecast for the middle of the afternoon. Our crossing of the Gatun Locks overlapped perfectly with a passing cargo ship, so we got to watch the whole process without having to wait for all the setup/approach/tug boat attachment, etc. It was surprising, really, just how quickly they can get such a large vessel through those things, once all the hardware is in place -- the boat was secured within the locks and being brought up to canal level within 10 or 15 minutes. When we pulled up to the Pina waterfront at around noon, the sun was shining, there was a nice breeze, the tide was giving us some space to work, and we were ready to go.
Our goal for the day was to finally remove a dolphin skull from a cliff that had been resisting us for the past few visits. We'd already carved out a nice deep trench around the thing and were confident it could be done in just a few hours. Since only so many of us can swing hammers and pickaxes at a time, two of us worked on carving out even more rock around the skull while the rest prospected and pulled out fossils from the tidal flats, including some turtle plastron and carapace and a some kind of really ugly manatee bone that to me looked completely unidentifiable and weathered to bits. Within an hour tragedy had struck hard over at the dolphin skull -- a certain blonde, six foot + someone had tried to chisel out a chunk of sandstone and ended up sending a crack straight through the fossil-containing boulder we had shaped out, halting all progress for fear of everything shattering to pieces. In all fairness though, it was probably bound to happen no matter what. The tide action is our friend in making it possible for us to break through the rock with our hand tools, but with the same hand it also weakens the matrix supporting the fossil, leaving it just as vulnerable and susceptible to breaks.

The plastered dolphin skull.

The fracture proved an opportunity for me to truly shine, for the only way to take care of a crumbling fossil is to wrap it up in a plaster jacket, something I got plenty of practice doing during my first month here! The tricky part in this particular job was that we only had plaster bandages and toilet paper. No foam or felt or saran wrap to protect the exposed bone. So rather than wrapping up the entire boulder as one normally would, I instead had to plaster around the circumference of the boulder and across the front only in those places where no bone was directly exposed, resulting in what basically looked like a half-finished job. With the equipment we had, it was the best that could be done. Frustratingly, the plaster was slow to dry due to the sea spray and the shadow provided by the cliff, and the waves were lapping at our feet before it had finished setting. We had no choice but to leave it for the next day and hope that the plaster would hold up. The bright side was that the next day we'd be able to bring a more complete set of plastering equipment, so we'd be prepared for the worst.

PCP-PIRE Pina Division

Of course, our little excavating crew (the local kids) were hanging around pretty much the whole time we were out working. Although school is back in session for them, they happened to have half a week off and were eager to use our tools, show us any sea life they were able to catch, and ask us questions about our personal lives. This time around they were particularly enthralled by our use of sunscreen and by the fact that none of us have children. There were plenty of opportunities for breaks and sitting around, since there was limited work space and lots of plaster dry time, so I spent a ton of time just hanging out with the kids having them teach me new words. At one point I pulled out my camera to take some pictures of my plaster work and they almost immediately gravitated towards it and insisted that I flip through all the hundreds of photos I've taken since I got here in January and explain what everything was. Doing so sure beat hacking at a rock wall with a pickaxe, so I was more than happy to oblige. They're some really good kids and even though I've only spent a couple of scattered days with them, I'm really going to miss seeing them when I return to the States.

The kids got a hold of my camera!

Postscript: I hurt my back overnight (how???) and when I woke up Wednesday I was without a doubt unfit for the field, so I took a lab day and watched everyone else head off towards beautiful Pina. From what they told me, they had to do the jacket all over again, though this time they had everything needed to do it properly. Again, however, there wasn't enough time between the tides for everything to set properly, so we'll be going back on Friday to finally retrieve that skull. It's causing all kinds of trouble for us!

Delays, delays, delays...

I was wrong! I thought we had finally fallen into a routine here, but I was totally off base. Turns out we've just been working on an extended temporary permit for all of March, and now we no longer have access. Here's a rough rundown of the situation: For the past four years or so, the Smithsonian and the Canal Authority have been working together through a joint contract that expired the first of this year. Under that contract, the Smithsonian received some amount of funding (I have no idea how much) for the work they were doing and would have to submit regular reports detailing what had been found and where for ACP's use in PR, historical documentation, etc. The group I'm currently working with (run through the University of Florida) knew the contract was nearing it's end and in the months leading up to 2013 repeatedly tried to get things moving with both the Smithsonian and ACP, since we're the only ones who would truly be affected by delays. Both organizations assured UF that there would be no problems at all and pushed negotiations off until the new year. Well, we're now in the fourth month of 2013 and no new contract has been agreed upon. Supposedly we can still access the Canal on a day-by-day basis (or week-by-week if we're lucky) by getting special permission the head environmental engineer, but we haven't been able to reach her for the past two weeks. So until that changes, lab days and spontaneous field trips are forecast for the foreseeable future. I'm not terribly upset about this because I've taken responsibility for cataloging all of our samples on an online database and up until now have basically had no spare time to actually do so!

Finally adjusted!

Two and a half months. That's how long it takes, apparently, to finally settle into the rhythm of things down here in Panama. Each day this week has felt completely ordinary and I've had a sense of "business as usual" to such an extent that it's felt like there's nothing even to write about. And it's been really, really nice! Of course it's tons of fun to always be doing new things and taking in new experiences, but it's also really tiring. Having a regular schedule as well as a sense of experience and know-how make each day run much smoother and helps the time pass more quickly, which is absolutely crucial now that we're moving into the wet season and each day is getting stickier and stickier. Without a doubt, we're still making cool finds, like a partial frog skull and a turtle pelvis, but nothing so spectacular that there's much more to say about it than simply what it is. I think in terms of the big-picture, evolutionary and migratory stuff we've found some rather interesting specimens, but lacking the biological background and having only a loose understanding of this region's history (I'm trying to catch up, but there's just so little time!), the wonder of such findings is lost on me. Nonetheless, it hasn't ceased being an exciting little kick whenever I pull something complete and identifiable out of the ground.

The one big piece of news (which I don't think I've mentioned yet) is that Aaron has returned to the University of Florida to carry out his research there and another post-doc, Jorge, has been sent in to replace him. This rotation is pretty ordinary, apparently, so that no one is required to move their entire life to Panama. Aaron will be coming back just a few weeks before the next round of interns begins. Although Aaron and Jorge are two very different people, the switch hasn't markedly changed anything, and so again is something that nearly slipped my mind to write about. For the most part, the only difference has been that Jorge's a bit more in the background than Aaron was, mostly because he's not yet familiar with the canal sites and so follows our lead instead of leading us. But even in just the five days that we've now all worked together, I can see the shift happening and it's obvious that he's quickly developing a sense for how everything fits together and where the most productive beds are.

There are only a handful of sites in the Canal Expansion Zone that consistently produce well-preserved fossils, so for the rest of my time here we'll basically just keep cycling through them, hoping that a good rain here or there might expose something new for us. On occasion we'll do something different, like spend a few days in Pina or survey and describe new localities as requested by the ACP (Autoridad de Canal Panama) geologists, but those tasks have now gone from being the norm to being the exception.

The Azuero Peninsula

As far as field work goes, I don't think this last week will ever be topped - we spent Sunday through Friday out on the Azuero Peninsula working almost exclusively at beach-front localities. Azuero is about a six hour drive west from Panama City and is dominated by agricultural and ranch land, with occasional towns and surfing destinations dotting the coastline. Even Las Tablas, the provincial capitol, wasn't much larger than any given neighborhood here in the city. Along with the usual crowd (Aaron, Sam, Nicole, Pedro, and I), a student from the University of Panama who volunteers at STRI (Sara) came along with us, making our group, thankfully, too large to all fit in a single truck. Those STRI trucks have been in use for quite some time, carrying dirty, sweaty geologists from one place to the next and it is not fun to get packed in tight and stuffy. Our goal for the week was to check out a few exposures that previous researchers had encountered and to do a bit of exploring ourselves to see if we could find any fossiliferous units exposed along stream beds or at roadside quarries. The entire peninsula is not terribly well described since there is so little exposure of the underlying rocks, but those sites that have been studied have all been dated to around 40 million years old (Eocene). This was an extremely casual trip, with no particular rush to leave in the mornings and no rigid expectations on fossil collection; we really didn't know whether we would find units overflowing with fossils or completely devoid of them. Best of all, the climate along the breezy coast, although still hot, was downright enjoyable compared to the stagnant air and oppressive sun along the canal. Definitely a much needed working vacation for all of us.

Sunday was mostly just a driving day. There's a quarry near the town of Ocu that Aaron had worked in before and found invertebrate and plant fossils, so we checked in to a hotel just on the outskirts Santiago (the nearest city big enough to have a hotel) and would go to the site in the morning. Because the quarry was on private land, Aaron and Pedro drove out to talk to the owner and get permission to collect, leaving the rest of us to bide our time at the air-conditioned, cable TV, pool-equipped hotel. Not such a bad gig! I was in the pool from the second I was able until the sun started to set and it was nothing short of fantastic. We really should consider getting one for our apartment. Oh! And the rooms had hot showers! Even though the water pressure was only a hair above a trickle, I savored every second underneath it - it was my first, and probably last, hot shower in Panama. Once Aaron and Pedro got back, we went into town for dinner then watched Wall-E in Spanish back in the hotel. If ever there were a movie to watch in a foreign language, Wall-E would be the one. Not a single one of us had any trouble following along.

The quarry. It was oppressively hot!

Monday morning at the quarry was rough. Even though we were out working by 8:00 AM, the heat of the day had already set in and there was little shade to be found. Plus we were out in the middle of ranch land, with cows easily spotted in any given direction, so the bugs were pretty thick. To top it all off, fossil abundance was pretty low and the preservation quality left something to be desired, so we ended up resigning ourselves to concretion-cracking to find anything of worth, which was hard, shrapnel-spreading work. Concretions are areas within the rock bed that have been selectively cemented with a mineral precipitate such as calcite or silica, and so are much more resistant to weathering and rock hammers. By the end of the morning we had a few seed impressions, some complete shells, and petrified wood, and decided to move on to the next site, which was just down the road, in a creek bed. There were conglomerates and sedimentary units that had been sampled for paleomag (a dating technique) by other researchers, within which we hoped to find some terrestrial remains, but to no avail. Still, hanging out under the tree cover and romping around in the cool water was a nice break from the open sun.

A little piece of croc tail we found in the stream bed.

Our next stop was also in a stream, one that wrapped itself around the city of Macaracas (very fun to say) and proved to be equally unfruitful. Past researchers had reported limestones in the area so we had hoped to find some marine fossils, and although we did manage to find the rocks, they were the deep variety of limestone, without a single fossil large enough to be seen with the naked eye. No fossils means no time spent digging around, so we had some time to kill and at first hoped to go for a swim in the stream, which in areas had pools deep enough to dive into, but after getting in close to the water, seeing the thick coating of green algae, picking up the strong smell of ammonia, and watching a group of cattle relieve themselves upstream, we decided against it. Not to mention there were posted signs prohibiting the use of beer-containing coolers. Where's the fun in that?

Thankfully, our last work stop of the day (also a stream, just outside the town of La Guerita) did have plenty of fossils, so the roadside stops weren't all for naught. This particular locality was probably my favorite; since it's the end of the dry season, the water level was particularly low and on the exposed limestone bed of the stream you could see where eddies whirlpools had weathered away the rock differentially, leaving behind some really cool patterns. No one found any bones, sadly, but we all found some pretty good looking shells of oysters and snails and scallops. Aaron and I, when exploring pretty far upstream from the road, found two enormous and complete oysters side by side in the limestone, and they were on a shelf that seemed eager to break off from the rest of the rock body (you could trace the beginnings of fractures all the way around. And, sure enough, breaking the shelf off wasn't hard work at all, but it left us with the dilemma of having to carry a 150+ lbs rock through a stream bed and then up a hill to get to the trucks, all for some shells. We decided that the only realistic way of taking the fossils with us was to chisel the sheet in half, leaving us with two much more manageable pieces to carry. The only problem was: that rock was HARD. My somewhat over-sized rock hammer didn't even come close to what we needed; the chisel just bounced off the rock with every hit. Our 6 lbs crack hammer had much the same effect. The only way we could make any real progress was with the giant sledge, and all it managed to do was chip away a few flakes here and there, forming a little crater around the chisel - there was no sign of any fractures developing. With the afternoon growing late and still a fair drive to go before getting to our hostel, we had to make one of the hardest choices of the whole trip and let our little baby go. Surely someone more suited for the challenge will come along and give those oysters the home they deserve.

Our hostel.

We checked in to our hostel at Playa Venao (playa = beach) just before sundown, which was the perfect time to take in the unbelievable setting we'd be living in through Friday. The hostel was tucked away maybe a quarter mile back from the water, and looked exactly like what you'd expect for a beach get-away. The frame of the building way made of what looked like driftwood, with whitewashed cinderblock-and-plaster walls, the roof was constructed out of palm fronds, all the furniture was handmade, varnished wood, and there were hammocks tied up everywhere. I never managed to get a picture that quite did it justice, but everything about the place said paradise. And the beach itself was nothing short of phenomenal! Venao is set in a little cove and is entirely sand, seriously not a stray rock or reef to be seen. And the slope into the water is so gradual that I could walk out at least 100 yards and still be able to touch the bottom. It's a surfer's dream too; perfect waves were constantly rolling in the entire time we were there. In fact, the world surf championships were held in Venao in 2011. To top it all off, Aaron informed us that the low tides would be between 4:00-6:00 AM and 3:00-5:00 PM while we were there, and since the morning low was before sunrise, we wouldn't have to "go into work" until the afternoon! This had the makings of a very, very fun work trip.

Hanging out at the beach on the first night.

Tuesday through Thursday were all more-or-less the same. I was up by 6:30 or 7:00 each morning due to the growing light and persistent rooster living under my window and tiptoed around my roommates to make my way out of the hostel and down to the beach. Pedro, Sam, Nicole, and Sara filled their room entirely, but Aaron and I had three extra beds in ours that were filled by ever-rotating surfers and backpackers. I was only out early enough to watch the sunrise on one occasion, and it was underwhelming - the whole coast is usually pretty overcast and foggy before the sun breaks it all up, so there wasn't really much to see. But I had a wonderful time regardless, either practicing some soccer (I bought a ball a few weekends ago) or going for a beach run before taking a long, long swim in the ocean. The runs couldn't have been much longer than 5K from one end of the beach to the other and back, but man did running in sand make my calves and achilles sore! I thought my legs were going to fall off at the knees before I ever made it back to Panama City. The swimming was also pretty exhausting, but far too much fun to ever notice it until I had crawled back on to shore. Aaron and I both spent a good hour or two each morning letting the waves crash into us, trying to swim through them, and trying to swim with them and body surf. I can definitely see why surfers love what they do, especially with waves as consistent as these.

Bucaro.

As for the paleontology side of things, every day at about 11:30 AM we'd drive out to Playa Bucaro for some shoreline fossil hunting, much like what we do in Pina. Bucaro is supposedly a surfing site too, according to the road signs, but the stretch of it that we were working on was all rocks, so I don't see that working out all too well. A good 2-3 hours on either side of low tide each day, we were out prospecting for marine fossils on the rocky shore. Theoretically, the tide changes should have made the job easy for us (just as in Pina), exposing all the fossil material and just leaving it up to us to find it, but it turned out to be like some kind of twisted version of Where's Waldo. We did find fossil material, and lots of it, particularly turtle carapace, mammal ribs, vertebrae, and teeth, everything was either exactly the same color as the surrounding rock or the same color and texture as it's neighboring non-fossil inclusions (pebbles, petrified wood, etc.). On top of that, the rocky beach was clearly a thriving intertidal habitat, so algae and crustaceans obscured everything. The more experienced members of the group (Aaron, Pedro, and Nicole) didn't seem phased by these features, but the rest of us had a hell of a time finding anything of worth. However, the challenge only served to make it feel that much better when I did stumble upon the small handful of fossils I collected over the three days. And there's really nothing to complain about when you're walking around on the beach all afternoon searching for bits of bone (and maybe doing some beach combing on the side...). Here are some of the highlights from Bucaro:

The sea turtle.

- We found a modern sea turtle carapace washed up and half-buried in the sand. It was enormous and in great condition, but, even as envoys of the Smithsonian, it was illegal for us to collect it or even touch it without express permission and permits.

- I saw a beached yellow-bellied sea snake on two separate occasions. When they wash up on the still-wet, compacted sand, they can't get enough traction to move and look as though they're on a snake treadmill. I wish I had taken a video! They're extremely poisonous (as are all sea snakes, apparently), injecting 2-8 times the lethal dose of venom for an average person in each bite. Despite this, Aaron took it upon himself to return both into the water using paired driftwood sticks. He's a brave on, no doubt about it.

- I found a modern vertebra that to my untrained eye looked like it had to have belonged to a whale or a dolphin (it was very similar to one I've been preping in lab), but when I showed it to Aaron in all my excitement, he told me that it was just from a cow, washed down a stream onto the beach. What a letdown!

- A stray dog followed us around all day on Wednesday, I think it was. He had the most enormous, goofy ears, was incredibly friendly, and actually looked to be in excellent shape for a roamer. The second you picked something up though (fossil or shell or whatever), he immediately went into play mode and wanted you to throw it for him. It was insanely cute, but pretty distracting and unproductive. At the end of the day, Sara fed him her leftover potato chips and Sam pulled a few ticks out of his ears - the poor guy had a ton of them!

- I found the washed up plastron (underside) of a modern soft-shelled turtle. It looks so cool! At first I thought there was only half of it, fractured right down the middle and wedged between a couple rocks, but just a few yards down the beach I found the other half just barely poking out of the sand. This one we did take back with us, since soft-shelled turtles are not endangered.

- On the last day we heard howler monkeys crying out from the hill overlooking our beach. We climbed up to check them out and in no time at all we had found the tree they were hanging out in. They were not happy at all to see us, and we soon realized that there was a newborn in their group so they were on high alert. I decided straight away to give them the space they wanted and didn't get any photos.

- On the last hour of the last day, as the sun was quickly disappearing behind a hill, Sam spotted a little piece of turtle carapace sticking out of one of the rocks and started to pick it out. The only thing was, it just kept extending deeper and deeper down, ultimately coming out at about the size of a large dinner plate. It took us at least 45 minutes past sundown to extract the thing and we all had to pull out our flashlights and watch carefully for developing cracks and movement as we finally pried it from the rock. It came out in just two pieces, the smaller only the size of a deck of cards, which I think was a job pretty well done, all things considered.

On Friday morning we headed home at around 9:00, and surprisingly I was the only one who got up early enough to fit in one last swim. How many times do you get to be on a beach in the tropics?? Not least one as garbage-free as Venao (Panama is notorious for having dirty beaches, particularly near the city). I may have been a bit sleepier than the rest during the ride home, but let's face it, ranch land all starts to look the same after the first few miles; I wasn't about to miss anything by taking nap or two here and there. The highlight of the trip home was stopping at a produce stand just before getting on to the Pan-American Highway, where I went a bit fruit crazy and bought a papaya, a watermelon, two pineapples, and a bunch of bananas. Good fruit was hard to come by out where we were! Can you blame me? There was a lowlight of the trip as well: one of the trucks broke down. Fortunately, we were only about an hour and a half outside of the city. If it had happened when we were way out on the tip of the peninsula, things would have been a lot harder. Aaron ended up sending the rest of us home in one truck with all the gear while he stayed behind to wait for the tow truck to pick him up. He got home about four hours later than we did, and in an attempt to make up for that we all pitched in and made a lasagna dinner (with wine, of course) that came out of the oven just seconds before he walked in the door. The timing couldn't have been better! Things also worked out in my favor with that lasagna - whoever was in charge of buying ground beef forgot to get it, so instead of making myself a personal veggie separately, we made one enormous VEGETARIAN LASAGNA. And they all LOVED it! Muahahahahaha. It was a fantastic ending to a fantastic week, even for Aaron, I think.

(Here's a quick map I made to show you most of the places we went to!)

Amazing fossil finds

Rock crater!

Artiodactyl molar found by yours truly.

I thought I was on my game early in the week with my slightly unhealthy fossil oyster obsession, but perspective is everything and I now know that Monday was nothing. Wednesday and Thursday were my real days to shine. Both were spent just across from the oyster site, at a terrestrial section that Aaron and Nicole had described earlier. On the first day, I was sent on a scouting mission to get as far up the hill slope as I could and to surface prospect for fossils in all of the beds I found on my way up. The difficulty in doing so was that part-way up the hill there was a plateau with a drainage running through it. Remember, we've been working in the canal expansion zone so we're actually below the water level of the adjacent Panama Canal. As a consequence, water is constantly being pumped out of the lowest-lying areas and all of it is eventually funneled into a kind of river that flows over our hill and back out into the canal. Since it's the dry season, the water wasn't very deep at all, nor was it very wide, so at first I had hoped to find a potential crossing. But once I got in close I realized there would be no hope of that - after five (or so) years of construction site water flowing through the area, the river's bed and banks were made up almost entirely of an ultra-fine clay mud that I instantly sank down in to. I poked some of the wetter-looking areas with a stick and was able to sink it in about three feet with virtually no resistance (as I continued to walk around looking for a crossing, I discovered that it was exceptionally fun to throw rocks into this mud and watch them disappear entirely). I did manage to find a way over to the other side though, by walking all the way to the far side of the hill where the "river" was piped under a service road. At first in all seemed to be for naught and I had no luck at all finding even the most meager of fossils, but finally, on my way back around to report to the group, I spotted a silver dollar-sized piece of turtle shell and a molar in some debris that had shed off from a conglomeratic layer! Aaron and the others drove the truck around to the service road to meet up with me and we had a wonderful afternoon finding tooth after tooth (mostly from horses and camels) as well as scattered turtle bones and even a partial rhinoceros jaw. I wish I could take credit for that one! When it came time to leave, I actually found myself sad to go and already anxious to return the next day.

And my anticipation was not unfounded! On Thursday we returned to the same hill and I made the greatest fossil discovery of my entire life. The pictures will speak for themselves, so all I'll say is that when I first spotted it, so little was exposed that I assumed it was only a tiny fragment. I couldn't believe my eyes as I continued to expose more and more of it - it seemed endless!

Less than this was exposed when I first saw it, but I was
too excited to think to take a picture.

The material came off incredibly easily.

There was a fracture running through one end, so I tried
to make everything more stable to avoid a break.

From above.

The final product: a scapula from a rhino.

Bonus content: mud cracks!

Real close up.

Back to the oysters

View from our work site.

Today I returned to the oyster site with just Pedro and Sam. All we had to do for the day was to measure and describe the section (which we were already quite familiar with from the day before) so Nicole and Aaron hung back in the lab to work on prep and curation stuff. I didn't exactly get a ton of sleep last night, so when I first woke I was seriously regretting not having volunteered to stay behind. This feeling only grew more powerful as I loaded up the truck with our equipment at 8:00 AM and could feel the humidity already starting to weigh down on me. Fortunately enough, my sullen attitude failed to drag the day down with me and I ended up having a really good time in the field.

The hardest part about our work for today was getting the initial general picture straight so that we'd know where to be careful and where to look out for unusual features. A lot of the outcrop was obscured by elephant grass (an invasive that grows like crazy and loves handing out scrapes and rashes to passersby) so a fair amount of digging and snooping was required to figure things out. After we had a rough idea of what was going on, Sam and I began measuring while Pedro described. Measuring is simple enough: it just involved figuring out the direction in which the plane of the rock beds extends into the ground then measuring perpendicularly up from that plane. The only challenge in it is determining what the planes are doing; what is seen on the surface is often deceiving and a true bedding plane is hard to come by (finding one that hasn't slumped is even harder). We use a tool called a Brunton (a glorified compass with some convenient bubble levels) to measure the angles of the bedding planes, and by getting measurements from multiple surfaces by multiple people, you can get an average that is pretty representative of the real situation. There ended up being about 50m of total section, and we were marking at an interval of no more than 50cm, so it took a fair bit of time to get the job done, but no real issues popped up.

Hand sample of the "cooked" sandstone.

For the most part, all there was to see along the section were alternating units of sandstone and siltstone, with the sands containing conglomeratic lenses and mollusk fossils, and the silts containing cemented burrows. The real points of interest in the area were two lengthy strips of metamorphosed sand that cut across the rest of the beds. We determined these to be evidence of alteration caused by hydrothermal injection into the already in-place beds. The metamorphosed sandstone went through a whole range of colors as you traced it from the bottom to the top of the hill and consisted of three main bands. The center band looked almost vesicular (holey), but on close inspection you could see that each hole was filled with a little ellipsoid of carbon (looked like miniature briquettes). On either side of that strip, there was a band of similar-looking sandstone that had thin carbonized plant fossils instead of the ellipsoids and was incredibly indurated - even with the pickaxe it was hard work to break it up. Finally, on the very outside, there were sandstones with large, disk-shaped grains, all aligned in more or less the same direction, still containing carbonized plants. The way we saw it, hot fluid must have entered a fossil-rich sandstone, cementing the rock hard and turning any organic matter into the ellipsoidal briquettes. The areas further away from the injection site did not get quite as hot, so groups of grains fused together rather than the entire rock body. Pretty interesting stuff!

Lots of cool mud cracks out on the flats below our section.

We had initially hoped to finish up in the early afternoon and get back to the labs early, but with the discovery of the altered areas it just didn't work out that way. We had to dig a couple of trenches in order to get good clean photos of the features and that was no easy work. Still, it was great geology so I think it's safe to speak for the group and say we all enjoyed it. Oh! And from the observations we made today, we feel pretty confident that the section represents a nearshore facies of the Culebra Formation, a ~23 million year old marine rock series that Pedro and Aaron have worked in before.

Ancient Oysters

This monstrosity was so large it would barely fit in your
palm. Found right where we were working :(

I was in the paleontological zone today! For whatever reason things just clicked and I couldn't get enough of prospecting/quarrying/sampling. With the field trip group safely back in Florida and no longer needing to be entertained, we visited a new site in the canal zone that had never been carefully examined or described before and set to doing just that. There were two main outcrops to focus on, one on either side of the vast pit that will eventually be a new channel of the expanded canal, basically right beside the Pedro Miguel locks. Aaron and Nicole went to measure and describe the western end, suspected to be a terrestrial, fluvial environment, while Pedro, Sam, and I did an initial observation and surface prospecting over on the opposite end, of which we knew very little. It didn't take long to conclude that we were in a shallow ocean/beach environment. The rock was a quartz-rich, well-rounded sandstone, and fossil oysters and petrified wood were everywhere to be found. Other minor fossils included some clams, fish vertebrae, limpets, and turtle bones. I don't know what it was, but something about the oyster fossils completely mesmerized me. The patterned layers of the shells, their textures, the colors, and the almost translucent appearance the inner surface has just struck me as so incredibly beautiful, despite their rather amorphous, unassuming shape. Long after we had collected enough representative fossils to please anyone, I was up on the outcrop looking for the blue/gray/white/pearl shells sticking out of the brownish sandstone. If a shell of any size looked to be at least 50% complete, I would swoop down on it, seeing if it had any characteristics to make it stand out from the others. There really is an immense range of color and patterns and textures within oyster shells. Some I was drawn to because they were so uniform and solid. Others because each individual sub-millimeter band alternated between dark and light. Others still for their metallic luster and impossibly smooth surface. By the end of the day I had two sample bags just for myself - much more than I'll truly be able to keep - but once I clean them up I'm hoping I'll be able to cut it down to just a handful. Never would have thought that I'd get hooked so bad on a spineless sea critter.

View of the canal from the highest point in the expansion area.

Under the bridge downtown

Yesterday, the last day our visitors spent with us, we worked directly underneath the Centenario Bridge in another Cucaracha Formation site (~20 million years old). It was a particularly important day for finding something interesting because we had a writer from the journal Science accompanying us - naturally, we wanted to impress him. Centenario is another quarrying site, where we dig pits at various fossil-rich contacts and hope that something interesting comes out. I lucked out and got to begin my day working at one of the quarries that was directly underneath the bridge's shadow. It's hard to say exactly how much cooler it was under there, but with the breeze and the lack of direct sunlight I can say with absolute certainty that it was damn comfortable. Unlike every other field experience I've had here so far, I wasn't sweating just from the effort of lifting my rock hammer. If I'd been able to, I would have followed that shadow for the entire day, working only under the protection it provided; sadly, the productive sights were concentrated northwest of the bridge, so I could only enjoy the lowered temperature for the early part of the morning. My particular pit proved less productive than I would have hoped, and by about noon I had found little more than a few broken turtle fossils.

View from the hill.

At just around noon I went on a tour of the canal sites (all of which I've described in previous posts) with Aaron, the writer, and the other interns. We showed him all of the places where we'd found the most interesting specimens and even did a bit of surface prospecting just for fun, resulting in the discovery of a couple shark teeth. The writer seemed pretty pleased with the day, so hopefully his article will reflect positively on the project and our part in it. Before leaving the canal expansion zone for the day, we took a road up to the highest point in the work site, a hill right next to the canal. There were some incredible views up there, particularly of the bridge towering over our site. It would have been a great place to have eaten lunch, or to have spent the entire day, for that matter.

Creepy "archaeological" discovery made near our work site.

In the evening, after returning from the field and cleaning up, we went to dinner in Casco Viejo (Panama's old town) to send off the field trip group in true style. The restaurant, called Diablicos, served up traditional Panamanian fare (which for me meant very few choices, but I didn't mind) and featured live dancers and a band playing musica tipico. The show was very fun to watch, and included dances with flowing skirts, torches, and devils. Plus they had some killer cocktails, including the coctel diablico, made from sugar cane juice, lemon, and rum - very delicious  Most of the dishes ordered included rice and beans and a salad made of potatoes and beets (supposedly very traditional), accompanied by large servings of meat or fish. Myself and the one other vegetarian in the group ordered a plate of ravioli topped with a sauce based in roasted sweet plantains and honey. The sauce was incredible and different from anything I've ever had, but the pasta itself was exceedingly bland, which brought the whole thing down. Still, everyone else seemed to enjoy what they had ordered, and the entertainment was A+, so I didn't let the noodles get me down.

It was a bit sad to see the field trip group go. I had gotten to know a few of them pretty well over the past week and they would have made great coworkers/interns/housemates. It can be hard at times being around the same five people 24/7 (all of whom I had never spent a moment around just two months ago) so it was nice to have the others here to mix things up.

Visitors from Florida!

Pretty much everyone in our group.

 In an effort to show the field trip group as much as possible and to make their Spring Break worthwhile, every day this week has been spent at a different locality looking for different kinds of fossils. It's been a nice change of pace and has helped the time to go by substantially quicker than usual. We'll be returning to these sites many more times in the coming months, so it was also helpful to be able to see them all in such rapid succession and to piece together the time and space relationships between them.

All the work sites have been right along the canal, near
the Centenario Bridge.

On Monday we drove down into the canal zone to a site called Las Cascadas, which is part of (oddly enough) the Cascadas Formation (~21 million years old) and contains terrestrial fossils. No collecting had been done there since early December, so we spent the first half of the day just surface prospecting, meaning that we looked for any signs of fossil material in the loose debris within stream channels, at the bottoms of slopes, and on the eroding surfaces of the exposed rocks. The hope was that some of the rain showers in the past few months might have washed out material and left it ripe for the picking. For the most part, there was little to be found, mostly just unidentifiable fragments of bone, but Nicole (fellow intern) manged to spot a nearly complete, though fractured, tooth that turned out to be from a taxa never before seen in this area. The tooth was a molar to some kind of horse-like animal with European affinities, and Aaron was entirely blown away when he saw it. It was pretty cool to be right there when a big discovery like that was made - I just wish I had been the one to spot it! That great find turned out to be the last, so in the early afternoon we turned to quarrying in some of the more fossiliferous beds, picking out palm-sized bits of rock with screwdrivers and busting them open to see if there was anything inside (fossil material causes weakness within the rock matrix and fractures will tend to open up along that weakness). Between the ten or so of us there, we found a few rodent teeth, some turtle carapace fragments, and an ankle bone of a small artiodactyl, a pretty good haul, I'm told, for that locality.

Teeth and a vertebra, all found by me!

On Tuesday we had the biggest group of the week: all six students from Florida, all five of my group, Bruce, and a researcher from CTPA (the geology/paleontology department of STRI) and her student. The researcher took us out to her main site of interest, called San Judas, which is part of the Gatun Formation (~10 million years) and is quite literally overflowing with marine fossils, mostly invertebrates. Our goal for the day was to collect a large quantity of well-preserved shells for an educational project Bruce is working on with some California school district. Any vertebrate remains were to be kept in a separate bag for use by the CTPA researcher. Like I said, this site had exposed invertebrate fossils as far as the eye could see, so within half an hour I had a quart sized bag full of bivalves, gastropods, worm burrows, barnacles, etc., all of which were basically perfectly preserved. Then I was free to focus on the fun stuff: shark teeth. And I was seriously on my game! Within an hour or less I had found five of those little suckers, more than anyone else in our enormous group. I think it must have been a fluke or something, since every other trip to the field has resulted in very poor finds for me. For whatever reason, though, the stars aligned at San Judas that day and I was able to bask in the glory of being a master fossil finder, at least for a while.

And after returning from the field we all went to the weekly seminar at Tupper, which was about the relationship between bats and plants. Much of the data was collected through high-quality video monitoring set up in Panama's own Bocas del Torro region, so we got to watch a whole bunch of really cool clips. The talk covered a lot of different aspects of how bats interact with plants, but two parts in particular stood out as really impressive and interesting. First, I learned that certain varieties of nectar-eating bats will turn to eating fruits during low-nectar or non-flowering periods, but they do not effectively distribute the seeds as would a true fruit bat. The speaker showed some footage of both types of bats eating the same varieties of fruits, and the nectar-eater would at first glance appear to eat in more or less the same way as the fruit-eater, just slightly less efficient. But when you zoomed in on the bats' mouths, you could see that the nectar eater was really only going after the juice; every few bites they would spit out a wad of pulp. In examining the discarded cores or certain fruit varieties, you could also see that the nectar eaters left much more behind to rot (and therefore not to grow) than the true fruit-eaters. Thus when these types of bats go to eat fruit as a necessity, they are essentially "cheating" the plant out of the arrangement it has with its more regular visitors. The other neat bit was that the quality of the footage allowed the researcher to see that in some cases bats served as transporters of other, smaller pollinators. In particular, there was a great video of a bat landing an a plant to drink from a flower and while it was busy you could see dozens of little white specks (flower mites) crawling from the plant onto its body and wings. When the bat went to roost in a nearby tree(they do this to rest and digest between feedings) you could still see the specks, but they were perfectly still. Then, when the bat moved on to another plant, you could see them all scurrying off. It was really incredible stuff!

Wednesday and Thursday were fairly low-key field days. We spent each at Hodges Microsite and Las Cascadas, respectively. Hodges is a part of the Cucaracha Formation (~20 million years) and is our most productive microfossil site, containing tons and tons of fish teeth, turtle fragments, croc teeth, rodents, bats, and much more. We pull these things out from a series of small quarries that have been found to be plentiful in the past, so each of us more or less just chose a hole to work in and started poking around. If I remember correctly, we didn't exactly walk away with a great haul, just a few scattered teeth and lots of broken bits. The quarries were all surrounded by eight feet tall elephant grass, however, so at the very least we had some comfortable shade to work in! Our return to Cascadas was similarly anticlimactic, with only a few ankle bones from artiodactyls (see above) to show for hours of digging.

The real highlight of Thursday, at least for me, was going once again to Barro Colorado Island for the dinner and seminar. Basically everyone mentioned above came along, so our group constituted a fair share of the attendees  The boat ride to the island was done on the small taxi this time, and it was pretty overcast and even a little rainy, so there weren't as many good opportunities for sight seeing as on my previous trip. That little boat got us to the STRI station a hell of a lot quicker than the cargo boat, though, which ended up paying off for us - we were the first ones to get to the kitchen area for the pre-dinner beer social, and so we were able to claim the balcony seats overlooking the shoreline. The sun even came out for us as we sat there! It was great. Dinner was pretty standard cafeteria fare, except they really went all out on the fruit, including some phenomenal papaya, pineapple, and watermelon  Plus there was a juice dispenser filled with Arnold Palmer to wash it all down. I was feeling exceptionally content by the time we had to head over to the conference room for the talk. The guest speaker was from Scripps and was all about coral reef systems. He laied out for us a bunch of his past experimental apparati for simulating a natural reef (tanks of ever-increasing complexity) then went on to show us what he is currently working on: a system for altering the local environment of an in-place reef in the actual ocean. This new in-situ system really blew my mind with how precise and responsive it could be, using computer-monitored pumps and injection tanks of super-saturated seawater to tune in to exactly the desired parameters (with emphasis on the effects of CO2 loading). Using his apparatus he was able to run some pretty convincing simulations of what the future might look like for coral reefs. For the most part, prospects are terrible, but there is hope in certain red branching corals that were able to alter their carbonate chemistry in order to deal with the simulated decreasing pH. It really was a thought-provoking presentation and I've been caught up in it ever since.

I made a friend back at the apartment :)