American Museum of Natural History

🦇Museum Curator of Mammalogy Angelo Soto-Centeno shares updates from his recent expedition to Puerto Rico, where he and a team of local and international researchers led a paleontological excavation and bat diversity inventory. The aim of this work was to explore new locations to examine the present, or living, and past, or fossil, communities of bats and identify species that have become extinct in recent times.

They found three species of extinct bats that were lost in the last 4,000 to 1,600 years—including insectivore and nectarivore bats!

Research alert! A new study shows how climate change affected the diversity of Congo River fish during glacial periods—crucial knowledge for understanding modern threats to fish in this species-rich region.

Over the last about 2.6 million years, polar ice caps have continuously expanded and retracted during glacial and interglacial cycles. This is thought to be a significant driver of biodiversity on land, but less is known about its effect on freshwater systems, especially in the Congo River. 

Using molecular tools, scientists focused on four species of fish endemic to the lower Congo River, known as lamprologine cichlids. Their findings, published in the journal Integrative and Comparative Biology, suggest speciation of Congo fish likely occurred when the river’s water level decreased, isolating populations of fish into smaller pockets of water, leading to the rise of new species over time. 

Learn more about how climate change impacts river fish.

Image: © Melanie Stiassny, Lamprologus lethops pictured

Research alert! A new study finds that an extremely well-preserved fossil of Triarthrus eatoni, a trilobite found in upstate New York, has an additional set of legs underneath its head! What did researchers learn from this discovery? Find out with Museum Curator Melanie Hopkins, who coauthored the research. Read more.

Research alert! A new study finds that an extremely well-preserved fossil of Triarthrus eatoni from upstate New York has an additional set of legs underneath its head. By making comparisons with another well-preserved trilobite species, Olenoides serratus from British Columbia, researchers from the Museum and Nanjing University in China have proposed a model for how appendages were attached to the head in relation to the grooves in the exoskeleton. 

“The number of these segments and how they are associated with other important traits, like eyes and legs, is important for understanding how arthropods are related to one another, and therefore, how they evolved,” said Melanie Hopkins, curator and chair of the Museum’s Division of Paleontology. 

Research alert! Two new fossils of a mouse-sized animal from the age of dinosaurs indicate that early mammals grew more slowly and lived longer than their modern descendants—rewriting our understanding of the lives of the very earliest mammals. An international study led by researchers at National Museums Scotland and published today in the journal Nature, compares two Krusatodon kirtlingtonensis fossils discovered decades apart in Scotland’s Isle of Skye. One of the fossils, the only juvenile Jurassic mammal skeleton known to science, was discovered in 2016 by Roger Benson, the Museum’s Macaulay Curator in the Division of Paleontology, and colleagues.

“These fossils are among the most complete mammals from this time period in the world,” said Elsa Panciroli, the lead author of the study and an associate researcher of paleobiology at National Museums Scotland. 

Learn how these small animals give us unprecedented insights into the lives of early mammals.

Image: © Maija Karala

The iconic frog-eating bat (Trachops cirrhosus), best known for hunting amphibians in the Neotropics, is one of the most easily recognizable bat species. But new research, led by Angelo Soto-Centeno, who is joining the Museum as an assistant curator in the Department of Mammalogy next month, along with Museum Curator Nancy Simmons and colleagues at the Universidade Federal do Espírito Santo in Brazil, suggests that these bats actually comprise three separate species across their range—knowledge that’s vital for future conservation efforts. 

“Frog-eating bats are very iconic and easy to identify, with long woolly fur, large ears, and wartlike protrusions on its chin and snout that make it very recognizable,” Soto-Centeno said. “But that has led to underestimation of its diversity. Detailed taxonomic accounts like this are the first step for making effective conservation decisions concerning these animals.”

Read more about their results, published today in the journal American Museum Novitates.

Photo: © Sherri and Brock Fenton

One small step for leeches, one giant leap for leechkind! For the first time, we have concrete evidence that at least one species of terrestrial leech in Madagascar can jump. Mai’s work is important to conservation efforts because leeches are increasingly being collected to survey vertebrate biodiversity. By analyzing their blood meals, researchers are able to identify other animals living alongside the leeches, ranging from wildcats to frogs to ground-dwelling birds. Read more about Mai's research in our latest blog post.

Have you ever seen a leech jump? Let us know in the comments!

Travel to Guyana with Anna Eichert and RJ Millena, Ph.D. students at the Richard Gilder Graduate School at the Museum. See how studying insect biodiversity helps scientists understand the impacts of climate change and other factors on these essential critters.

By studying calcifying organisms, Leanne aims to better understand the impacts of human activity on marine ecosystems. Through her research, she hopes to influence policy that helps protect marine calcifiers in the future.

“Why is this important? The idea is that the more porous the shell, the weaker it is. Mussels need strong, robust shells to protect their inner soft organs—and that strong 3D structure is important for ecosystem function as habitat formers and storm defenses.

Currently, the changes seen in shell porosity are not large enough to influence the material properties, so we aren’t seeing weaker shells just yet. But with further warming in our oceans being predicted, this could potentially lead to even more porous shells, potentially impacting mussels’ function as habitat formers and storm defenses, as well as their ability to protect themselves from predation,” Melbourne explains.

Learn more about her research here.

Research alert! A team of international scientists has discovered the largest known freshwater dolphin, an ancient species that lived in the Peruvian Amazon some 16.5 million years ago. Pebanista yacuruna, which likely measured 10-11.5-feet (3-3.5 meters) long, inhabited what is now the Amazon River basin before this system had its major connection to the Atlantic Ocean. 

“Discoveries by our international collaborative teams tell us the kinds of tropical life that existed during times in Earth’s history when virtually nothing had been known before,” said John Flynn, the Museum’s Frick Curator of Fossil Mammals and a co-author on the new study, which was published in the journal Science Advances. “This is crucial to understanding the history and pathways that led to the remarkably rich modern Amazonian biodiversity.” 

Learn more about this animal, and its surprising modern relatives, in our latest blog post.

Trilobites are extinct animals that have a shell made of “rock”—and sometimes, these animals record examples of failed predation within their suit of armor. New research by Russell Bicknell, a postdoctoral researcher in the Museum’s Division of Paleontology, examined unique specimens that showcased extreme examples of such injuries. These rare fossils show how trilobites were often at the bottom of the food chain and were food for bigger animals. These specimens also provide important insight into how trilobites recovered from failed predation.

Image 1: Paradoxides bohemicus Image 2: Close up of Paradoxides bohemicus injury Image 3: Ogygopsis klotzi Image 4: Close up of Ogygopsis klotzi injury Image 5: Olenoides serratus Image 6: Close up of Olenoides serratus injury

Photos courtesy of Russell Bicknell

Research alert! Imagine putting flippers on a 24-foot Komodo dragon. That’s how Amelia Zietlow, a Ph.D. student at the Museum’s Richard Gilder Graduate School, describes Jormungandr walhallaensis, a newly identified species of mosasaur that was named in part after a sea serpent in Norse mythology.

Living some 80 million years ago during the Cretaceous, this mosasaur is thought to represent a transitional period between other well-known species. In addition to flippers and a stumpy, shark-like tail, Jormungandr had a bony ridge on its skull that would have given it the appearance of having “angry eyebrows.”

🕷️Meet Joe Arguelles, a comparative biology Ph.D. student in the Museum’s Richard Gilder Graduate School. His research focuses on understanding the molecular drivers of the incredible mechanical properties of spider silks.

🕸️He also studies the evolution of “prey capture systems” (silk, venom, and vision) in active hunting spiders, and how these genes have changed in response to the loss of web-spinning behavior.

New research alert! In 2019, Museum researchers David Gruber and John Sparks were diving in the icy waters surrounding Greenland when they discovered that the variegated snailfish (Liparis gibbus) glows. This tiny snailfish remains the only polar fish reported to biofluoresce. Now, in a recently published study, they have uncovered something else surprising: this fish contains the highest expression of antifreeze proteins ever observed. It also sends up a red flag about how these highly specialized animals might fare in warming environmental conditions. Read more about their findings with the link in our bio! Photos: © John Sparks and David Gruber #museums #research #NewResearch #fish #biofluorescence #ichthyology #Greenland #ClimateChange #ClimateAndNature #MarineBiology #STEM #science #amnh https://www.instagram.com/p/ChVNOQavHUe/?igshid=NGJjMDIxMWI=

📰NEWS: T. rex is still king! A recent study led by paleontologists at the American Museum of Natural History, the @edinburghuniversity, and @carthagecollege refutes a provocative claim made earlier this year that fossils classified as the dinosaur Tyrannosaurus rex belong to three separate species. 🦖The rebuttal, published in the journal Evolutionary Biology, finds that the earlier proposal lacks sufficient evidence to split up the iconic species. Read more about their findings with the link in our bio. #news #research #paleontology #trex #tyrannosaurusrex #tyrannosaur #dinosaurs #museums #amnh https://www.instagram.com/p/CghRwtWLFV0/?igshid=NGJjMDIxMWI=

🚨#NewResearch alert! A recent study co-authored by Museum Senior Research Scientist Jackie Faherty highlights 34 “ultracool” dwarfs, also known as brown dwarfs, that were discovered by a citizen scientist from the Backyard Worlds: Planet 9 citizen science project. 🔭Brown dwarfs are star-like, with more mass than planets but less mass than stars, which makes them much harder to spot. The question of how often stars exist alone is an enduring question in the field of astronomy, and for brown dwarfs, the answer to this question is especially elusive. But these discoveries could help astronomers determine if brown dwarfs are more akin to oversized planets or undersized stars, as well as providing insights into how star systems evolve over time. Read more about their findings in the link in our bio! Image: NOIRLab/NSF/AURA/M. Garlick #research #STEM #science #space #astronomy #CitizenScience #CitizenScientist #amnh #museums #BackyardWorlds #planets #stars #BrownDwarf https://www.instagram.com/p/CfuM79VPTmz/?igshid=NGJjMDIxMWI=

🦒How did the giraffe’s long neck evolve? 🔬New research co-authored by Jin Meng, a curator in the Museum’s Division of Paleontology, complicates previous theories. In the past, many agreed that the giraffe evolved its long neck to reach foliage and outcompete others in the search for food. In 1996, a set of researchers offered a “necks-for-sex” hypothesis, suggesting sexual selection driven by intermale competition may have also contributed to neck evolution. Now, newly described 17-million-year-old fossils from a new species of Miocene giraffoid named Discokeryx xiezh are offering new evidence about why giraffes have long necks. 📑Read more about Discokeryx xiezhi and the findings, recently published in the journal Science, in the link in our bio. #giraffes #AnimalFacts #paleontology #research #NewResearch #amnh #dyk #nature #NaturalHistory https://www.instagram.com/p/CeY0BVxr4YQ/?igshid=NGJjMDIxMWI=