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Russell Waines’ stromatoporoid collection

Waines’ stromatoporoid collection is housed in metal cabinets with wooden drawers at the UCMP. Photo courtesy of author.

Figure 1: Waines’ stromatoporoid collection is housed in metal cabinets with wooden drawers at the UCMP. Photo courtesy of author.

Russell H. Waines was a geologist who dedicated most of his life to ancient sponges, the stromatoporoids, which were one of the most important reef builders during the Paleozoic. When I was a graduate student researcher at the UCMP in 2013, I had the pleasure of organizing this collection (Figure 1), which includes approximately 2000 fossil specimens (566 of which are registered in the UCMP database) mainly from the Devonian of Nevada, but also from Alaska, Arizona, California, New York, Utah, Washington, the San Juan Islands, and Ontario. In addition to the fossil specimens, this collection has 910 slides (Figure 2) prepared by Waines during his dissertation work.

Russell Waines got his Ph.D. in Paleontology from UC Berkeley in 1965, under the supervision of J. Wyatt Durham. For his dissertation work, Waines performed a taxonomic study of the Devonian stromatoporoids from Nevada, which included four of the five stromatoporoid families: Labechiidae, Clathrodictyidae, Acrinostromatidae, and Idiostromatidae. He also revised the stratigraphic zones for the Upper Devonian and proposed a new zone using stromatoporoids as bioindicators.

Figure 2: This collection houses 16 boxes with the slides from cross sections of the specimens. On the right are images of some of these slides. Photo courtesy of author.

Figure 2: This collection houses 16 boxes with the slides from cross sections of the specimens. On the right are images of some of these slides. Photo courtesy of author.

Figure 3: Drawings of the cross-sections from four of his “new species”. Photo courtesy of author.

Figure 3: Drawings of the cross-sections from four of his “new species”. Photo courtesy of author.

Waines’ dissertation is a great monograph that includes a thorough morphological analysis of 30 stromatoporoid species with drawings of their cross-section (Figure 3). Impressively, 28 out of the 30 species analyzed by Waines were unknown to science and still are (Figure 4)! His dissertation was never published; therefore, the species described by him are not considered valid by the International Commission on Zoological Nomenclature. This collection is a great resource for stromatoporoid workers and if his species analyses were accurate, there are 28 new species in the UCMP drawers just waiting to be properly formalized.

Following his Ph.D., Russell Waines was hired by the New Paltz State University of New York where he retired in 2006. During his career, he published 13 scientific papers and 24 conference abstracts. His stromatoporoid works include:

Fritz, M.A. & Waines, R.H. 1956. Stromatoporoids from the Upper Abitibi River Limestone. Proceedings of Geological Association of Canada 8:87–126.

Waines, R.H. 1960. Stromatoporoids of the Kennett Limestone, Shasta County, California. Geological Society of America Bulletin 71(12):2081.

Langenheim, R.L., Jr.; Carss, B.W.; Kennerly, J.B.; McCutcheon, V.A. & Waines, R.H. 1962. Paleozoic section in Arrow Canyon Range, Clark County, Nevada. AAPG Bulletin 46:592–609.

Wilson, E.C.; Waines, R.H.; Coogan, AH. 1963. A new species of Komia Korde and the systemic position of the genus. Paleontology 6(2):246–253.

Waines, R.H. 1964. Devonian stromatoporoid faunas of Nevada. Geological Society of America Special Paper 76:230–231.

Waines, R.H. 1965. Devonian stromatoporoids of Nevada. Ph.D. dissertation, University of California, Berkeley. 505 p.

Figure 4: Images of two “type” specimens described by Waines in his dissertation. He gave temporary UCMP numbers to all “new” specimens he described; the top image, for example, shows a “paratype” with the temporary number UCMP 11120, which has been now changed to UCMP 13982. Locality numbers (e.g. B9405) were not changed. Most of the specimens are also cut to make slides. The bottom image shows a “holotype” that has been cut: the code A-83-R refers to the slide with its cross-section (apparently A-83 refers to a group of specimens from the same locality, and R refers specifically to this specimen), and the number 10 refers to this taxon. Photo courtesy of author.

Figure 4: Images of two “type” specimens described by Waines in his dissertation. He gave temporary UCMP numbers to all “new” specimens he described; the top image, for example, shows a “paratype” with the temporary number UCMP 11120, which has been now changed to UCMP 13982. Locality numbers (e.g. B9405) were not changed. Most of the specimens are also cut to make slides. The bottom image shows a “holotype” that has been cut: the code A-83-R refers to the slide with its cross-section (apparently A-83 refers to a group of specimens from the same locality, and R refers specifically to this specimen), and the number 10 refers to this taxon. Photo courtesy of author.

UCMP paleobiologists shed new light on ozone shield failure, forest sterility, and mass extinction

Conifers-under-UV-B-lampsMembers of the Looy Lab - Jeff Benca, Ivo Duijnstee, and Cindy Looy - co-authored a paper in the journal Science Advances.  It details exciting new findings from experimental research on the effects on UV-B induced stresses on forest decline during the end-Permian extinction.

Read more in the University press release.

View the video:

A new destination for disaster enthusiasts

The Deccan Traps today. Photo courtesy of Mark Richards

The Deccan Traps today. Photo courtesy of Mark Richards

The Cretaceous-Paleogene (K-Pg or K-T) mass extinction — the event in which the non-avian dinosaurs, along with about 70% of all species in the fossil record went extinct — was probably caused by the Chicxulub meteor impact in Yucatán, México. However, scientists have long wondered about the massive volcanic eruptions that were occurring in northwestern India at about the same time, the Deccan Traps. Volcanism is the likely cause of several prior mass extinctions, with no convincing evidence for impacts. Was the aligned timing of these events at K-T time (asteroid impact, extinction, and volcanism) pure coincidence? I am part of a diverse research team, which includes UCMP associates Paul Renne and Walter Alvarez, working on an NSF-funded project that seeks to answer this question using many different lines of evidence.

We are more precisely dating Deccan lavas, analyzing new rock samples from onshore field work and offshore drilling, and performing geophysical modeling in an effort to figure out how an asteroid impact, a mass extinction, and volcanism might or might not be tied together. Work so far suggests that the main phase of these volcanic eruptions, the largest of the past 100 million years of Earth history, correspond with ever-increasing precision in time with the Chicxulub meteor impact in Yucatán, México, and therefore also to the extermination of the non-avian dinosaurs and about 70% of all species in the fossil record 66.04 (+/-.03) million years ago. The tantalizing implication is that the meteor impact caused a factor of 2-3 increase in the lava flow rate, greatly increasing the likely environmental damage from release of volcanic gases and aerosols. Thus, the alignment of these disastrous events does not seem to be coincidental!

I’d like to invite the UCMP community to follow our ongoing research on our new websitewhere we will present the activities and scientific results of our project to explore the nature, physical mechanisms, and precise timing of the Deccan Traps flood basalts. There, we will keep you up to date with our fieldwork, geophysical modeling, geochemical and geochronological analyses, and our database and publications, as well as highlight the many individuals involved in the project, including graduate students, postdocs, and a number of distinguished international collaborators. Come visit us at disaster central: https://deccan.berkeley.edu/

Researchers Tushar Mittal, Courtney Sprain, Loÿc Vanderkluyson, Paul Renne, me (Mark Richards), and Kanchan Pande visiting a step well near our field site in Ahmedabad, Gujarat State, India. The carved stones behind us are not Deccan basalts, but they are very impressive!

Researchers Tushar Mittal, Courtney Sprain, Loÿc Vanderkluyson, Paul Renne, me (Mark Richards), and Kanchan Pande visiting a step well near our field site in Ahmedabad, Gujarat State, India. The carved stones behind us are not Deccan basalts, but they are very impressive!

A Pleistocene pit-stop: the Barnosky lab excavates Natural Trap Cave, Wyoming

You might think that an 85-foot-deep hole where a bunch of horses, wolves, camels, elephants, and plenty of other animals accidentally plummeted to their death over tens of thousands of years would have enough red flags to make going into it yourself sound like a bad idea. But what if these unfortunate critters could tell you what their life was like and how they died? What if they could give you a warning about their death in a warming world after the last ice age and what it means for life in a warming world today? And, most importantly, what if you could fall and climb back out very slowly on a controlled rope system with an expert team of cavers and paleontologists? This past summer we decided to do just that: Barnosky lab members Eric Holt and Nick Spano with alums Susumu Tomiya and Jenny McGuire joined a crew led by Julie Meachen (Des Moines University) to descend into this “Natural Trap” Cave, excavate ice age mammal fossils, and help advance our understanding of how life responds to climate change, all without contributing any extra bones.

Natural Trap Cave is a 12-foot wide by 85-foot deep hole at the top of a hill in the Bighorn Mountains on the Wyoming side of the Montana border. The entrance to the cave is difficult to see coming down from the ridge of the hill behind it, so it’s not surprising that many Pleistocene ‘megafauna’ (animals bigger than 100 lb. or 45 kg)  accidentally fell to their demise here over tens of thousands of years ago. As they fell into Natural Trap Cave, their bones formed a well-stratified and mostly undisturbed pile that has become internationally renowned since the 1970s for its paleontological significance. The cave had been closed by the Bureau of Land Management (BLM) for over 20 years to protect the fossils from theft. However advances in ancient DNA research and growing interests in what Pleistocene extinctions could tell us for conservation prompted it to be reopened by Julie Meachen’s group for further research. This site is ~42 °F at ~98% relative humidity year-round, making it an ideal refrigerator for extracting 30,000 year-old genetic material. Geographically, it is located just south of a gap that existed between the Laurentide and Cordilleran ice sheets in central North America at the last glacial maximum (LGM) ~22,000 years ago. The ice-free corridor extended all the way up to Alaska and provides a unique opportunity to investigate continental migration dynamics, population genetics with ancient DNA, and climate-driven community changes.

This past summer, Eric and I (Nick Spano) drove 18 hours from Berkeley, CA to join a volunteer crew of paleontologists and cavers led by Julie Meachen at Natural Trap Cave in Wyoming. To enter the cave, each person needs to rappel down a rope hanging 85 feet down into the cave. Even if you claim to be unafraid of heights, the first descent is still slightly nerve-wracking. Stepping backwards off of the cave’s rim into a black pit with only a constellation of faint headlamps at the bottom can be a little unsettling. Plus, easing your grip on the rope here to let out slack takes a couple days to become comfortable with.

 

Descending

Eric Holt descending down a ladder towards the ‘edge of no return’.

Once you start the descent through increasingly colder temperatures, a council of packrat (Neotoma) middens along an inner rim welcomes you to the cave. After the initial shock of dangling passes and your eyes adjust to the low light, you get a sense for just how open and surreal the bell-shaped chamber is. I could only imagine what it must have been like for whole bison, horses, and wolves to fall that far down as I gracefully descended to the cave floor. Because we were searching for fossils of all sizes--from bison to mice teeth--we had to look carefully while excavating. That said, a fossil would pop out of the sediment about every ten minutes, which kept things pretty exciting.

horse cannon bone

Horse cannon bone found by Nick Spano. Dental pick for scale.

excavation

Eric Holt carefully excavating a bison dentary to be field-jacketed.

Bison dentary up-close.

Bison dentary up-close.

Once discovered, each fossil needed to be tagged with information about which animal it came from, where in the cave it was found, and what kind of sediment it was found in. We then bagged the specimens and bulk sediments to be screen-washed for microfossils and hauled them back to the surface in a bucket on a rope. In that sense, we were lucky we didn’t find anything bigger than the bucket. Once the excavations were complete, the site was remediated to protect exposed sediments from further weathering and to leave the site in a pristine state for future paleontologists.

screen washing

Eric Holt with a set of drying screen-wash screens.

Now that the final and most recent field season has ended, Natural Trap Cave is closed again for the foreseeable future. Susumu is going through identifications and Jenny is analyzing microfossils from the site. This study will provide a greater understanding of how life was changing in a warming world at the end of the last ice age, with implications for how life might respond to current and projected warming. Eric and I are very thankful to have been volunteers involved with this project and are looking forward to some great results.

Banosky Lab at NTC

Barnosky lab members outside of Natural Trap Cave. From left to right: Nick Spano, Jenny McGuire, Eric Holt, and Susumu Tomiya.

What do traces of predators tell about ancient marine ecosystems?

Reconstructing biotic interactions is crucial to understand the functioning and evolution of ecosystems through time, but this is notoriously difficult. Competition in deep time cannot be readily seen except for overgrowth of one organism by another under the assumption that both were alive at the same time. Parasites usually do not preserve because they are soft-bodied and tend to be small so that they are not spotted easily. The most abundant evidence of biotic interactions comes from the study of predators and the traces they leave. In the marine fossil record, drill holes in a variety of shelly organisms made, in part, by carnivorous snails are ubiquitous and become increasingly common toward the present. The oldest recognized predatory drill holes are as old as ~750 million years and found in micro-organisms. Some quarter billion years later in the early Phanerozoic, brachiopods and other small shells show some drill holes now and then. Starting in the Cretaceous and into the Cenozoic the percentage of shells, primarily mollusks then, with a predatory drill hole increases. This rise coincides with the appearance and diversification of snails such as members of the Naticidae and Muricidae families. Today, these snails use acids and enzymes to weaken and dissolve part of the shell followed by the removal of the affected part by many rows of razor-sharp teeth. This is a very laborious process because the drilling speed is only 0.01–0.02 mm/h!

Predatory drill holes in ~4 million-year-old bivalve and gastropod shells from the Netherlands. Not only mollusks, but also other organisms such as crabs can be victims of drilling predators. Check out this spectacular video! First and last image from Klompmaker (2009, PALAIOS). Scale bar width = 2.0 mm.

Predatory drill holes in ~4 million-year-old bivalve and gastropod shells from the Netherlands. Not only mollusks, but also other organisms such as crabs can be victims of drilling predators. Check out this spectacular video! First and last image from Klompmaker (2009, PALAIOS). Scale bar width = 2.0 mm.

These predatory drill holes, already recognized by the Greek philosopher and scientist Aristotle over 2300 years ago, have been studied by paleontologists for over 100 years, but an increasing number of studies have been published since the 1980s. One aspect that was completely unknown until recently is the size of these drill holes through time. From some individual modern driller species, it is known that larger specimens produce larger drill holes. This is no surprise because the drilling apparatus grows with age. However, whether this is true too when modern driller species are combined was an unresolved matter. Modern drillers are found among many families of gastropods, but some octopuses, insects, foraminifera, nematods, and other micro-organisms also can bore into their prey. It was very exciting to see that there is a significant positive relationship between driller size and drill-hole diameter. Why so? This relationship can now be leveraged to infer trends in the relative size of predators through time by studying the size of drill holes in shells. This is particularly useful because the identity of drillers is poorly known prior to 100 million years ago. Additionally, predator-prey size ratios can be estimated as well when both drill-hole diameter and prey size are measured.

The percentage of shell area that is drilled (a measure of predator-prey size ratios) throughout the Phanerozoic. Modified from Klompmaker, Kowalewski, Huntley & Finnegan (2017, Science).

The percentage of shell area that is drilled (a measure of predator-prey size ratios) throughout the Phanerozoic. Modified from Klompmaker, Kowalewski, Huntley & Finnegan (2017, Science).

Due to the increasing body of literature over the last ten years and renewed search into older literature, I expanded an existing database regarding data on drill-hole size by a factor nine and added prey size where possible. Finally, there was enough data to look at possible trends throughout the last 500 million years! But no trend showed up for the size of drilled prey shells, primarily brachiopods and mollusks. Conversely, an obvious rise is evident in the drill-hole diameter as the median hole increased as much as an order of magnitude from 0.35 to 3.25 mm. Combining these two metrics yields the percentage of the shell area that is drilled, which is a measure for predator-prey size ratios here. These ratios show a quite spectacular increase of medians from 0.05% to 3.5% over the last 500 million years. These results imply that predators became larger while their prey did not, which is further supported by the fact that putative early Phanerozoic drillers are statistically smaller than late Phanerozoic gastropods that have modern representatives that do drill. Furthermore, these results back an important tenet of the escalation hypothesis, that predators have become more powerful over evolutionary time.

We think that these increasing predator-prey size ratios can be explained by substantial changes on the sea floor. Although prey size did not change, the meat content of drilled shell did. Brachiopods were the dominant prey prior to 250 million years ago. These animals contained little meat in their shell, certainly much less than the mollusks, which became more abundant in the last quarter billion years and dominate drilled prey shells. Another major change is that the density of prey increased through time as suggested by independent studies. Thus, drillers did not only obtain more food per shell, but also may have encountered more prey items! Both factors may have contributed to the evolution of increasingly larger predatory drillers. A last factor that may be important is predation among predators, which can lead to higher predator-prey size ratios according to ecological models. Evidence for increased predation among predators is supported by the fossil record as drillers themselves become drilled more frequently starting in the Cretaceous - early Cenozoic. A larger size of drillers may have also helped as a defense against shell-breaking predators such as crabs and fish that became more common throughout the Phanerozoic. This study exemplifies that long-term biotic interactions can be reconstructed and highlights the importance of such interactions in ancient marine ecosystems.

Summary diagram. Credit: Karla Schaffer / AAAS

Summary diagram. Credit: Karla Schaffer / AAAS

This research would not have been possible without the many case studies of colleagues on which the database hinges and fruitful collaborations. This study was presented at the annual Geological Society of America meeting with financial support from the UCMP and was published this June.

Klompmaker, A. A., Kowalewski, M., Huntley, J. W., & Finnegan, S. (2017). Increase in predator-prey size ratios throughout the Phanerozoic history of marine ecosystemsScience 356 (6343): 1178–1180.

Understanding the evolutionary history of the cassiduloid echinoids

Photographs of Rhyncholampas gouldii (Bouve) (Cassidulidae) in aboral, oral and posterior view (from left to right).

Figure 1: Photographs of Rhyncholampas gouldii (Bouve) (Cassidulidae) in aboral, oral and posterior view (from left to right).

It is widely recognized that major groups evolve at different rates, in their own evolutionary trajectories. Some evolve fast and are very diversified while others evolve slowly and may never experience an explosion of diversity throughout their trajectory. One of my research interests is understanding the pace of morphological evolution through time, and the organisms selected to investigate this topic are the irregular echinoids.

Commonly known irregular echinoids include the sand dollars (clypeasteroids) and the heart urchins (spatangoids). They are called “irregular” because they evolved morphological innovations that depart from the “regular and pentaradial symmetric” type, seen in the sea urchins. Most of these innovations evolved convergently in different groups and are mostly adapted for their infaunal (i.e., burrowing) life style. For instance, irregular echinoids usually have a flattened test with thin spines that are more adapted for burrowing. They also evolved petals with specialized tube feet for breathing, their anus moved away from the apical disk possibly to avoid waste released near the petals, and they lost the Aristotle’s Lantern as adults and feed on the detritus in the sediment. Finally, irregular urchins have an anterior-posterior polarity and are said to have a secondary bilateral symmetry (the larvae has primary bilateral symmetry). Irregular echinoids evolved during the Mesozoic Marine Revolution and these morphological modifications are just a small part of their interesting evolutionary history! In addition, they live worldwide, their fossil record is excellent, and the major groups display very contrasting evolutionary histories.

Figure 2: Drawings of cassiduloid structures (on the left, the mouth and oral plates and phyllopores [i.e., pores where the tube feet specialized for feeding are found]; in the right, the oral ambulacrum II).

Figure 2: Drawings of cassiduloid structures (on the left, the mouth and oral plates and phyllopores [i.e., pores where the tube feet specialized for feeding are found]; in the right, the oral ambulacrum II).

Besides the sand dollars and heart urchins, there are three other groups of extant irregular echinoids: the holectypoids, echinoneoids and cassiduloids. One of the reasons you have probably never heard about them is that they are rare. My research focuses on the cassiduloids (Figure 1; some known as lamp urchins). Cassiduloids probably originated in the Cretaceous and reached a peak of diversity in the Eocene, when they composed about 40% of all echinoid genera. After the Eocene, their diversity declined sharply and today only about 30 species are known. Although their fossil record is very species rich, the cassiduloid morphology appears to be quite constrained. Few novelties evolved throughout their long evolutionary trajectory (as opposed to the heart urchins), and the species found today are mostly endemic and restricted to certain kinds of environments (e.g., mostly warm waters and with coarse grain sediments).

The classification of the cassiduloids is very controversial, and it has been shown that they may not compose a monophyletic group. Therefore, the first step of my research is reconstructing a time-calibrated phylogeny of the cassiduloid echinoids that will allow me not only test the relationship within the group but also to understand how the major cassiduloid groups relate to the other irregular echinoids. In addition, a phylogeny will allow me study the evolution of major innovations within the group, their rate of morphological change, and their patterns of biogeographic distribution through time. Because of the rarity and poor preservation of the cassiduloids in museum collections, I am focusing on the morphological data. Most of the characters analyzed focus on the plate patterns of the test, which can be seen in well preserved fossils, and I am also obtaining micro-computerized-tomography (i.e., 3D) images of extant specimens at the Lawrence National Berkeley Laboratory to find novel characters that are difficult to see with stereo-microscopes (Figure 2).

Many of the specimens included in my analyses are deposited at the UCMP and at the California Academy of Sciences. However, most of the extant cassiduloids are very rare and restricted to one or two scientific collections; and some are known only for their type specimens. To analyze such taxa I often have to visit these collections. After analyzing the specimens deposited in the Bay area museums, last summer I started exploring specimens deposited elsewhere.

Figure 3: Photographs of the Australian Museum building depicting a T-rex (head and tail can be seen coming out of the windows), of my Australian favorite terrestrial animals — the rainbow lorikeet and a kangaroo, and a record of my first time on the West Pacific ocean.

Figure 3: Photographs of the Australian Museum building depicting a T-rex (head and tail can be seen coming out of the windows), of my Australian favorite terrestrial animals — the rainbow lorikeet and a kangaroo, and a record of my first time on the West Pacific ocean.

My first stop was Australia (Figures 3–4). The Australian Museum in Sydney and the Melbourne Museum were chosen not because of the diversity of cassiduloids present but by the uniqueness of the species found there, both in the invertebrate and paleontological collections. One of advantages of visiting collections instead of asking for loans is the surprises we often find. For instance, I found a misidentified specimen in the Australian Museum whose species was known only by its two co-types. This specimen not only provided me with more information on the morphological variation of this species but also increased its known geographic range. I also had great surprises on the Melbourne Museum, where I could analyze two specimens that they had recently obtained and therefore were not present in their database. Besides analyzing cassiduloid species I had never seen before, I also met Frank Holmes, an amateur paleontologist who works in the Melbourne Museum and shares my passion for the cassiduloids. Frank has described cassiduloid species and we had great discussions over an undescribed Paleocene cassiduloid he is working on!

Figure 4: Photograph of the Melbourne Museum building (top left), of the Queen Victoria Market (a “must go” place in Melbourne according to the natives; bottom left), and of me and Frank Holmes in the paleontological collection (image on the table is of the new Paleocene cassiduloid) (right).

Figure 4: Photograph of the Melbourne Museum building (top left), of the Queen Victoria Market (a “must go” place in Melbourne according to the natives; bottom left), and of me and Frank Holmes in the paleontological collection (image on the table is of the new Paleocene cassiduloid) (right).

My next and final stop was the Smithsonian Institution National Museum of Natural History (NMNH) in Washington D.C. (Figure 5). Visiting their echinoderm collection was one of my dreams as an undergrad, not only because this collection houses the great majority of specimens I have always needed to analyze, but also because of the great researchers who have worked there, such as Theodore Mortensen, Elisabeth Deichmman, and Porter Kier. Their echinoderm collection is divided into three collections: the dry collection and the paleontological collection are housed in the main building in Washington D.C., and the wet collection is housed at their Museum Support Center in Suitland, Maryland (Figure 5). So I often travelled back and forth between these collections and focusing on the cassiduloid was not hard at all. There were just so many of them!!!

Figure 5: Photograph of the NMNH building (top left), of my workstation at the Museum Center in Suitland (bottom left), and of myself with the oversized echinoderms in the wet collection (right).

Figure 5: Photograph of the NMNH building (top left), of my workstation at the Museum Center in Suitland (bottom left), and of myself with the oversized echinoderms in the wet collection (right).

Figure 6: Book of the Springer room visitors; in detail, a record of the visit of the UCMP Director Charles Marshall in 1989 to analyze clypeasteroid echinoids (i.e., sand dollars)!!

Figure 6: Book of the Springer room visitors; in detail, a record of the visit of the UCMP Director Charles Marshall in 1989 to analyze clypeasteroid echinoids (i.e., sand dollars)!!

The NMNH echinoderm paleontological collection in particular surprised me for having its own room! The Springer room is dedicated to Frank Springer, an amateur paleontologist who donated a significant  echinoderm specimens (most of which are crinoids, Frank Springer’s favorites) and literature to the NMNH. The preservation of many fossils in the Springer room is superb and captures a great level of detail. The cassiduloid collection, for instance, is very diverse and is composed of fossil specimens from all over the world. This abundance is probably a result of Porter Kier’s work on the “Revision of the Cassiduloid Echinoids”. For most of the species, I could even choose five or more of its best specimens, a privilege I have never had in any other collection.

The Springer room also has one of the best libraries on echinoderm paleontology in the country, together with Porter Kier’s jacket, and a book of signatures which has recorded all history of visits in the room. Among these, I found the signature of the UCMP director Charles Marshall (Figure 6)!

At the end of my journey, I analyzed 47 cassiduloid species (eight extant and 39 fossils; about 150 specimens, including 13 type specimens). All this data was integrated into a morphological matrix, and the phylogenetic analyzes will be performed when I analyze all specimens chosen.

Surprising new finds in museum specimens

The author measuring lizard specimens at the AMNH in New York City.

Figure 1: The author measuring lizard specimens at the AMNH in New York City.

I am very grateful to have received a UCMP Graduate Student Research Award via the Barnosky Fund in April 2016. I used these funds to collect pilot data from major natural history museum collections around the country for my dissertation research.

My research investigates responses in fossil animal communities to climate change over long time intervals. We need historical data about the affects of climate change on animals in the past in order to anticipate these affects on animals in the future. I focus on reptiles because we already know that climate affects the appearance and habits of reptiles today. We do not yet understand how this relationship affects the evolution of reptiles over long periods of time. I am examining the fossil record of reptiles in North America through the Paleogene, a period that lasted from about 66 to 23 million years ago (Mya). The planet experienced major warming and cooling during this time, and North America has an excellent fossil record spanning the same interval.

Over the last year, with support from UCMP funds, I sampled fossil collections at the Field Museum of Natural History in Chicago, IL; the Smithsonian National Museum of Natural History in Washington, D.C.; the Denver Museum of Nature and Science in Denver, CO; the Boulder Museum of Natural History in Boulder, CO; and the American Museum of Natural History in New York, NY (Fig. 1). I measured and photographed 330 fossil lizard and 150 fossil crocodylian specimens, representing over a dozen intermontane basins in the Western Interior of the U.S.

I also made a surprising discovery at the Denver Museum: a fossil lizard specimen showing distinctive signs that the tail broke off and had started to grow back. This is the earliest evidence of tail regeneration in a fossil lizard. It suggests that armored lizards were evading predators by dropping and re-growing their tails as early as 50 Mya.

Figure 2. Specimen DMNH 16950. Fossil lizard tail showing signs of regeneration. Scale bar = 1 cm.

Figure 2. Specimen DMNH 16950. Fossil lizard tail showing signs of regeneration. Scale bar = 1 cm.

Over the next year, I plan to sample several more museum collections to complete my dataset. I will run statistical analyses to examine patterns of response to climate change in reptile communities over a span of more than 40 million years, and compare these results to documented changes in reptile communities today.

Thank you to the UCMP for supporting my research!

A Hitchhiker’s Guide to the Pleistocene Sea

Using Fossil Whale Barnacles to Reconstruct Prehistoric Whale Migrations

A fossil humpback whale barnacle, Coronula diadema, that we recently found in Plio-Pleistocene deposits of Panama.

A fossil humpback whale barnacle, Coronula diadema, that we recently found in Plio-Pleistocene deposits of Panama.

Baleen whales, as we know them today, lead lives that are largely defined by their annual migrations. Every year, whales spend their winters breeding and reproducing in tropical waters, then travel to poleward feeding areas each summer. For North Pacific humpback whales, winter breeding areas cluster around Central America and Hawaii, and then they travel to the Gulf of Alaska to feed in the summer (small numbers also feed on the California coast). Likewise, gray whales travel from Baja California to the Bering Sea. These are the longest migrations made by any mammal, and they come at extreme energetic costs, as a whale will lose 25% of its body weight between summer feeding sessions.

Because of this cost, whales rely on taking in enormous amounts of food each summer, and thus they are tracking down the most productive areas of the ocean. In a sense, the migration routes of whales tell us something about ocean productivity and how it’s distributed, both in time and in space. This is where things get interesting: perhaps whale movements in the prehistoric past can yield clues about ocean productivity patterns millions of years ago. What’s more, being massive allows whales to afford this type of lifestyle: they have enough energy stores to last through the lean seasons, and their great size allows them to travel the thousands of miles necessary to reach their summer feeding areas. This link between body size and lifestyle has led some scientists to believe that it’s not just coincidence, and that perhaps whales are so big specifically because they evolved to better handle the demands of migration.

Larry Taylor in the field in Panama, getting ready to chisel a fossil whale barnacle out of the rocky outcrop he’s sitting on.

Larry Taylor in the field in Panama, getting ready to chisel a fossil whale barnacle out of the rocky outcrop he’s sitting on.

Can whale migrations of the past tell us something about productivity and nutrient distribution in the ancient oceans? Did whales really get so big because they evolved to migrate? Both of these questions rely on figuring out if whale were migrating in the past, and if so, how those migrations changed through time. My research seeks to answer these questions by taking advantage of fossil whale barnacles. Whale barnacles incorporate stable isotope signatures of the surrounding seawater into their shells, and as they grow, they continually deposit new shell beside older shell. That means that their shells end up with an isotopic signature of the water they’ve been growing in over their life. As it turns out, this signature can be decoded to give clues about where in the ocean each shell layer was formed. Thus, a whale barnacle acts like as a tracking mechanism, recording signatures of everywhere its host whale has been traveling.

My approach is relatively straightforward: I collect samples of shell powder from a barnacle by drilling into it, then these samples are isotopically analyzed by UC Berkeley’s Center for Stable Isotope Biogeochemistry. I then use an equation derived by Killingley and Newman (1982) to help reconstruct where the barnacle (and the whale it was riding on) has been. I first tried this approach with modern barnacles to verify the technique, and found that barnacle isotope profiles accurately reconstructed the migration of humpback and gray whales, including humpbacks that take multiple different migratory routes. Now my advisor, Seth Finnegan, and I are working purely in the fossil record, using specimens that have been loaned by museums as well as fossils we recently discovered in Panama. Results thus far are promising, as some of the fossil isotope profiles retain basic patterns also seen in the modern barnacles. There is a lot of work left to do, but these preliminary results give me confidence that we can extract useful information from the fossil barnacles. With luck and proper analysis, this work will shed light on just how prehistoric whales were moving, and what that means for the evolution of the ocean and of the whales themselves.

This work is generously supported by grants from the UC Museum of Paleontology, National Sigma Xi, the Berkeley Chapter of Sigma Xi, the Geological Society of America, the Paleontological Society, and by collaborators from the NOAA, the San Diego Natural History Museum, the California Academy of Sciences, the Smithsonian Tropical Research Institute, and the National Museum of Natural History.

Doing field work on the Panamanian coast yielded more benefits than just the exquisite fossils. Our field site was an eroded coastline, and we were awarded with incredible views.

Doing field work on the Panamanian coast yielded more benefits than just the exquisite fossils. Our field site was an eroded coastline, and we were awarded with incredible views.

Bringing the field to our users through EPICC’s Virtual Field Experiences

Ever wonder where fossils from the UCMP were collected or want to know more about the geological setting of UCMP field areas? Curious about why an area looks the way it does?

These questions and others are driving the development of Virtual Field Experiences (VFEs) associated with the EPICC project (Eastern Pacific Invertebrate Communities of the Cenozoic, http://epicc.berkeley.edu). Together with EPICC partners from the Paleontological Research Institution (PRI), UCMP Assistant Director Lisa White and Museum Scientist Erica Clites joined Robert Ross (PRI Associate Director for Outreach) and Don Duggan-Haas (PRI Director of Teacher Programming) to document field areas along the west coast serving as the basis for Cenozoic invertebrate fossil collections that are being digitized with support from the National Science Foundation (as part of the Advancing Digitization of Biological Collections program).

The EPICC partnership with nine natural history museums focuses on Cenozoic fossils found in the eastern Pacific. Within California, fossils from the Kettleman Hills in the Central Valley of California and fossils along the Pacific coast will be part of a series of VFEs designed to document and capture the field to museum connection. These connections provide an opportunity for our users to explore the geological backdrop of our Cenozoic invertebrate collections and learn how fossils are described and interpreted.

As a preview of the VFEs, which will go live in late spring, follow us into the field as we document fossils in context, highlight sedimentological features, and describe unique structures in the Purisima Formation along the California coast. During several days in March 2017, the UCMP and PRI team went to key locations along Capitola Beach (Santa Cruz County) and Moss Beach (San Mateo County) to photograph rocks and fossils, and videotape the team at work.

The primary goal of the VFEs is to show how paleontological field work and fossil data collection are done.

In these series of photographs taken at Moss Beach (the Fitzgerald Marine Reserve), view the team at work, capturing and documenting the source of some EPICC fossil collections.

 

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The team crosses a rocky stretch of beach in to inspect which sections of the Purisima Formation would be ideal for photography. At low tide, most visitors to the Fitzgerald Marine Reserve go to enjoy the tide pools and the organisms of the rocky intertidal zone.

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The team begins setting up at one of the Purisima Formation outcrops.

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The Purisima Formation, between 3-7 million years old, contains an array of fossil bivalves and other invertebrates. Here, among the shell fragments, is a fossil bivalve shown in life position in this cross sectional view.

Set up for filming the videos

Videographer, John Tegan setting up the shot with Rob and Lisa to discuss key features of the landscape.

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Don scanning the outcrop and capturing images in 3D.

Erica, for scale, describing some different textural features in beds of the Purisima Formation.

Erica, for scale, describing some different textural features in beds of the Purisima Formation.

Beds of the Purisima Formation are folded into a plunging syncline. UCMP Staff Assistant Lillian Pearson hops across for a better view.

Beds of the Purisima Formation are folded into a plunging syncline. UCMP Staff Assistant Lillian Pearson hops across for a better view.

Some of the shells are concentrated into highly fossiliferous sandstone and conglomerate beds, dense with fragments of bivalve and gastropod shells, with occasional echinoids and other fossils. The shells are highly fragmented and are embedded in pebble conglomerate suggesting these may be storm beds.

Some of the shells are concentrated into highly fossiliferous sandstone and conglomerate beds, dense with fragments of bivalve and gastropod shells, with occasional echinoids and other fossils. The shells are highly fragmented and are embedded in pebble conglomerate suggesting these may be storm beds.

 

Making these experiences more accessible.

UCMP and the Paleontological Research Institute will keep working together with all the EPICC partners to bring paleontological and geological experiences to the classroom through these virtual field experiences. We are enthusiastic about offering these educational tools and sharing the stunning geology of California and the west coast. We think the VFE will be especially helpful for communities who don't have ready access to outdoor spaces.

Once these VFEs are completed, they will be shared on the EPICC website. www.epicc.berkeley.edu

 

Cryptic caves and paleoecology of crustaceans in Cenozoic coral reefs

Just some months ago on a Saturday in July, I had the pleasure of snorkeling above the only coral reefs in the continental Unites States. These reefs in southern Florida still harbor many species of corals, fish, and other animals including crustaceans such as crabs, shrimps, and lobsters. These decapods are difficult to spot while snorkeling, but that does not mean they are not there. Their usually small size in this landscape of incredibly variable topography ensure they are able to hide effectively from predators. As for many other animals, coral reefs are a hotspot for decapod biodiversity. This was by no means different in the distant past. The rapid diversification of crabs and squat lobsters in sponge and shallow-water coral reefs during Late Jurassic is one of the best examples. When many reefs vanished in the earliest Cretaceous so did many of these crustaceans, highlighting the need to protect corals and, in doing so, also the associated, often cryptic animals.

One example of these cryptic animals are crabs from the Cryptochiridae family. Today, over 50 species are known of these tiny animals that have a carapace of less than a centimeter long. They do not hide in the rubble or between coral branches, but they create their own homes within the corals. Their home is either a true gall or a tunnel that is either circular/oval or crescentic in cross-section. Despite their high biodiversity, no convincing cryptochirid fossils were known until very recently.

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The modern cryptochirid crab Troglocarcinus corallicola sitting snugly in a crescentic home in the coral Manicina areolata. Scale bar width: 50 mm for a, 5.0 mm for b. Source: Klompmaker, Portell & Van der Meij, 2016, Scientific Reports

Earlier this year, an open access article together with Roger Portell and Sancia van der Meij was published showing superbly preserved crescentic-shaped holes in Plio- and Pleistocene corals from Florida and Cuba. No animals other than cryptochirids create such holes so the culprit of this trace fossil was easy to identify. Unfortunately, no crabs were found inside the holes because these relatively soft and tiny crabs do not preserve well. Such crescentic holes should be present in more fossil corals all over the world. Why? Cryptic crabs that make such holes are found in corals in nearly all (sub)tropical regions of the world today. Additional evidence would help tremendously in constraining the antiquity of this family and with getting a better sense about their past biodiversity. So check out your fossil corals at home or in a museum nearby! Some places in the world expose fossil coral reefs as a good third alternative.

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Pleistocene corals from Florida: Solenastrea bournoni (a, b) and Solenastrea hyades (c˗e) with close-ups of crescentic cryptochirid holes. Photo d shows the holotype of the trace fossil named after this particular shape: Galacticus duerri. The genus name is derived from Battlestar Galactica because of the similar cross-sectional shape of this battleship to these crescentic holes. Scale bar width = 50 mm for complete corals; 10 mm for close-ups. Source: Klompmaker, Portell & Van der Meij, 2016, Scientific Reports

That's exactly what I did in the summer of 2014, but for different reasons. I was lucky to receive funds from the Paleontological Society (Arthur James Boucot Research Grant) and a COCARDE Workshop Grant (European Science Foundation) to travel to Denmark to a very special fossil coral reef in the famous Faxe Quarry. This quarry is accessible to everybody and it certainly is a great place to visit when you are in Denmark as is the Geomuseum Faxe right next to it! My Danish colleagues Bodil Lauridsen and Sten Jakobsen helped to find the right places for collecting. The exposed coral and bryozoan mounds were living at 200-400 m depth in dim light conditions in the earliest Cenozoic (~63 million years ago). Such deep-water coral reefs can still be found all over the world up to depths of 1000+ meters by the way.

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The Faxe Quarry at dusk after a long field day.

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Author (right) with colleague Sten Jakobsen (left)

This complex reef at Faxe also contains decapods, primarily crabs and squat lobsters. After more than a century of collecting, as many as 25 species are known. That’s a lot right? However, well-sampled, shallow-water fossil coral reefs from elsewhere in Europe contain even more decapods.  The Cretaceous-Paleogene extinction event that wiped out the non-avian dinosaurs, ammonites, and severely affected many other groups has apparently nothing to do with the lower decapod diversity at Faxe. Our analyses show that decapod diversity is not affected by this event. Instead, less food and perhaps fewer hiding places have contributed to this lower diversity. A comparatively low decapod diversity is also seen in today’s deep-water coral reefs.

These critters may differ also in body and eye size compared to their shallow-water friends in corals reefs. The crabs at Faxe tend to be larger for half of the analyses, whereas other results show no difference. Some ideas about the reasons include a lower number of predators, a delayed maturity, and an increased life span of these crustaceans in deeper, colder waters. Quite spectacular evidence was found when we compared the eye socket size (true eyes are not preserved) for crabs of the same size and genus from Faxe to those from a shallow-water reef. While initial results did not seem to show much, a closer look at the data and additional measurements did show a distinct difference. The eye sockets of the crabs at Faxe are larger than those from a shallow-water reef! Thus, these crabs evolved larger eyes to see better in the dim light conditions in Faxe ~63 million years ago.

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Leftover rocks from a number of days of field work at one of the sites in the Faxe Quarry.

Some crabs can be readily seen in the wall of the quarry. Here an example of a partially exposed carapace of Dromiopsis rugosus.

Some crabs can be readily seen in the wall of the quarry. Here an example of a partially exposed carapace of Dromiopsis rugosus.

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Carapaces of crabs and some squat lobsters (c, d) from the Faxe Quarry in Denmark and some crabs from Spain (g, h). a. Dromiopsis rugosus; b, Dromiopsis elegans; c, Protomunida munidoides; d, Galathea strigifera; e & f, Caloxanthus ornatus; g & h, Caloxanthus paraornatus. The eye socket height of many specimens of the two species of Caloxanthus was compared. Scale bar width: 5.0 mm for a & b; 2.0 mm for rest. Source: Klompmaker, Jakobsen & Lauridsen, 2016, BMC Evolutionary Biology (open access)

The incredible biodiversity of fossil decapod crustaceans with ~3500 known species, many of them known from reefs, still results in the description of tens of new taxa each year by professionals and avocational paleontologists, often during collaborative efforts. With such data becoming more and more available, studies on diversity and paleoecology have become more common in recent years. The collection of the UCMP also does hold many, yet to be studied fossil decapods. Research on this exciting group of crustaceans continues!