Panama Day 9: Lago Alajuela and Tupper Talk

On tap today:

Lago Alajuela

STRI Tupper seminar: Fossil Lianas and the History of Miocene Rainforests in Panama by Nathan A. Jud.

Caption: this is “a trip the average person doesn’t get to do! I want to sweat.” John Turner. This is the site where about 55 years prior he found a Gomphothere tooth; here he has designed a dredge to try to collect more fossilized treasure!

Grab your water and electrolytes folks, this day promises to pack a punch. Our predicted high is 89* F with humidity at 87*. We should have a 2mph breeze to help keep us cool.

This is our third and last time at Lago Alajuela. Joining our crew today, we have Sean Matson, as our photographer, and Ornithologist Dr. George Angher, who basically wrote the book on birds of Panama.

Bruce McFadden, Sean Matson in blue hat, Dr. George Angher in background

Before heading off into two smaller groups Bruce gave instructions. Group 1, was to stay crack rocks and focus on the stratigraphy of the lake shoreline. Group 2 was to head out to a few of the smaller islands that we could see from shore with sediment outcrops, and browse.

To the islands we go!

As we were waiting for our dugout to arrive, Myra Codera, Nathan A. Jud and I found small fossilized sharks teeth. Bruce told us not to browse on shore, as we had already been to that site but we could not help ourselves!

With GPS or IPhone in hand, life jackets and our packs we piled into Rolando’s boat. Over the course of the next two hours we browsed 5 islands in total, found a few interesting specimens, and listened to Rolando recount stories of growing up in this area, discoveries of fossils found on islands when the water level was low, he discussed water shortage, water contamination, and the effects of the Panama Canal on the Panamanians. Rolando was a fantastic guide.

On one island I found a shark’s fossilized dermal scute, we observed an adorable Collared Plover baby, and saw lots of rock, some which appeared to be the type that

Dr. Richard Cooke referred to the day before when we paid him a visit, and a modern day turtle skull.

Two of the five islands had trees on the top strata, whereas the other three were primarily small grasses and volcanic rocks of varying sizes.

Coordinates of one of the islands

Questions to explore, posed by Bruce:

How do sediments on islands compare to sediments on shore?

How do fossils fit into the stratigraphy?

How old is the basin?







What about the Crew that stayed on shore?

A few sites were visited. At site two Sean Matson found the ankle bone of a tiny deer-like animal. Is it modern? If not, we could add this to the fossil record.

On our way up the hill, away from the lake, I hung close to Nate Jud. This is where I learned about an epiphytic fern from the family fern polypodiceae.

Nathan A. Jud showing off epiphytes










Tupper Talk

Nathan A. Jud

Paleogene and Neogene tropical forest of Panama: new insights from fossil woods

17I learned that the Neotropic fossil record is sparse: 1918 Berry, 1980 Graham, and PCP-Pire recently. In general, we want to understand the history of tropical rainforests to shed light on our current diversity.

Nathan Jud discussed why fossil woods are a good tool, and global patterns.

As far as the Alajuela formation is concerned, we do not know a lot about this prior to the onset of GABI. It has shallow marine deposits, is the only late Miocene vert. site One can find the following families: Malvaceae, Amnonaceae, Sapindaceae, Arecaceae( palm trunks), and Chrysobalanaceae. I will google these names later!

From the Alajuela formation 9 wood samples have been collected, and one palm sample. The Samples have vessels of moderate diameter, and are typical of dry forests.

What does this mean? If I understood correctly, according to Nathan Jud, seasonally dry tropical forests and co-occurring horses and gomphotheres , might mean that we could find evidence of grass lands at around 9.7 Ma.?

Truth be told, I have always loved trees, I am drawn to their beauty but also to all that they offer. Our first two days at Alajuela, the bulk of what I found was fossilized wood. When Bruce caught hold of my fossil wood windfall, he said that I might be interested in meeting Nathan A. Jud! Shadowing Nathan in the field at Lago Alajuela was so much fun, and educational! We learned what fossil woods were good to collect and which to leave. Nathan helped us to identify our finds.

Our descent to Lago Alajuela was through modern day tropical rain forest. Before we set off fossil hunting, Nathan was nowhere to be found. I figured that he must be stuck up trail, observing the abundant flora; he was. It was so great to work alongside someone who is so passionate about what they do. I agree with John Turner , “ this IS a trip the average person does not get to do!”

I am excited to design lessons, using fossils we have collected, information learned from talks and from fellow teachers, scientists, professors, and interns. This has been a great learning experience, working side by side in the field and out. Thank you all for providing such an enriching experience.

After a long day in the field under the hot sun, we refueled here, reflecting on yet another successful day in Panama.

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