Museum researchers discover earliest use of Mexican turkeys by ancient Maya

September 14th, 2012

By Danielle Torrent

Erin in Lab

Erin Thornton analyzes ancient animal remains in the lab.
Photo by Dan Thornton

As a University of Florida graduate student, one of Erin Thornton’s first assignments was to identify turkey bones from an ancient Mayan archaeological site in Guatemala.

Determined to please her adviser, Thornton thoroughly examined the features of the bones, which dated to the Late Preclassic period from 300 B.C. to A.D. 100. She decided they were remains of a non-local turkey native to central and northern Mexico, Meleagris gallopavo gallopavo, commonly known as the Mexican Turkey.

But unbeknownst to Thornton at the time, her conclusion defied previous archaeological evidence – the species did not belong in the Maya area during the Late Preclassic period. According to the archaeological record, the Maya did not use the non-local Mexican Turkey until about 1,000 years later.

“To be honest, I was so focused on getting the morphological identifications correct to impress my doctoral adviser that I wasn’t necessarily thinking about what species should or shouldn’t be there in the Late Preclassic,” said Thornton, a research associate at the Florida Museum of Natural History on the UF campus and Trent University Archaeological Research Centre in Canada.

Thornton then consulted the Museum’s resident bird expert, ornithology curator David Steadman, who confirmed the identifications. But they needed additional evidence. So Steadman, Thornton and her adviser, curator of environmental archaeology Kitty Emery, collaborated with DNA analysts to verify the bones belonged to the Mexican Turkey, representing the earliest evidence of the species in the Maya world.

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Museum researchers name new ancient camels from Panama Canal excavation

August 1st, 2012

By Danielle Torrent

Museum researchers recently discovered this lower jaw of Aguascalietia panamaensis, a new species of ancient camel from Panama. © Florida Museum photos by Jeff Gage

When it comes to camels, it’s difficult not to think of the Old World depicted through Arabian Nights – Bedouin travelers crossing vast, radiant deserts by day, through dark, star-spotted Arabian nights. But according to the fossil record, the ancestors of modern camels were creatures of the New World.

Based on fossils from the North American Great Plains, the earliest-known camels dwelled in the American savannah about 35 million years ago. It was a time before the formation of the Isthmus of Panama, when the continents of North and South America were still separated by the oceanic waters. But despite the separation of the continents, recent Panama Canal excavations by Florida Museum of Natural History researchers show ancient camels similar to those in North America also thrived in Central America 20 million years ago.

“We’re discovering this fabulous new diversity of animals that lived in Central America that we didn’t even know about before,” said Florida Museum vertebrate paleontology curator Bruce MacFadden, co-principal investigator on the National Science Foundation grant funding the Panama Canal project. “Prior to this discovery, they [ancient camels] were unknown south of Mexico.”

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Museum lepidopterist discovers new endemic species in disturbed habitats of Hawaii

July 1st, 2012

By Danielle Torrent

Florida Museum assistant curator of Lepidoptera Akito Kawahara recently described three moth species in a ZooKeys study published in February 2012.© Florida Museum photo by Kristen Grace

On the Hawaiian Islands, where isolated, vulnerable pieces of land are surrounded by thousands of miles of ocean, habitat destruction is something of a catchphrase.

It is well known how the arrival of humans about 1,000 years ago drastically changed the ecosystem with the introduction of invasive plants and animals. It has led to stricter policies for releasing non-native pets, increased regulations at trade ports and the emergence of restoration ecology, in which scientists strive to re-create a more native environment.

But within areas seemingly overcome by invasive plants and animals, one Florida Museum of Natural History lepidopterist discovered three new native moth species.

“The mountains in Hawaii look really beautiful, but most of the plants in the lowlands are not supposed to be there,” said Akito Kawahara, assistant curator of Lepidoptera at the Florida Museum, who led a study published in the February 2012 edition of ZooKeys. “If you think about that, it’s really shocking to find some rare, endemic species in an area where these are not typically supposed to be found.”

Kawahara described new species of an unusual genus commonly known as fancy case caterpillars. Similar to how snails carry a shell, the caterpillars wear different ornate “cases” throughout the larval stage of development.

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Earliest horses show past global warming affected body size of mammals

June 1st, 2012

By Danielle Torrent

Florida Museum researcher Jonathan Bloch compares the upper jaw of Sifrhippus, the earliest known horse species (foreground), to the upper jaw of a modern-day horse. © Florida Museum photo by Kristen Grace

These days, climate change is a hot topic.

What will happen as temperatures rise more rapidly than humans have documented in modern history? Will birds and mammals flock or will they be able to acclimate? Who will become extinct?

In recent years, scientists have strived to understand the atmosphere’s balance of greenhouse gases to create models that predict rapid climate change, a process humans have accelerated with deforestation and the burning of fossil fuels. Scientists at the Florida Museum of Natural History and anthropology department on the University of Florida campus explored the issue by studying an extreme short-term global warming event known as the Paleocene-Eocene Thermal Maximum that occurred about 56 million years ago.

During this 175,000-year climate event, increased concentrations of carbon dioxide in the atmosphere and oceans caused average global temperatures to rise 10 to 20 degrees.

“The PETM is really important because it marks the beginning for the first appearance of several major groups of mammals, including crown-group primates (ancestors of modern primates) and the first even- and odd-toed modern ungulates (mammals with hooves),” said associate curator of vertebrate paleontology Jonathan Bloch, co-author of a study published in Science Feb. 24, 2012, that correlates temperature with mammalian body size. “This sets the scene for the entire diversity of animals we see on the planet today.”

The study shows how mammals responded to past climate change: As temperatures increased, their body size decreased.

Researchers focused on the evolution of Sifrhippus, the earliest-known horse, which first appeared in the North American fossil record during the Paleocene-Eocene Thermal Maximum. By analyzing the size and isotopes of fossils collected in Wyoming’s Bighorn Basin, researchers traced the evolution of Sifrhippus from an estimated 12-pound animal that shrank during a 130,000-year period about 30 percent to 8.5 pounds, and then increased to about 15 pounds during the next 45,000 years.

“Horses started out small, about the size of a small dog like a miniature schnauzer,” Bloch said. “What’s surprising is that after they first appeared, they then became even smaller and then dramatically increased in size, and that exactly corresponds to the global warming event, followed by cooling. It had been known that mammals were small during that time and that it was warm, but we hadn’t understood that temperature specifically was driving the evolution of body size.”

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Coastal forests retreat as sea levels rise

May 1st, 2012

By Francis E. “Jack” Putz

Turtle Creek; Withlacoochee Gulf Preserve. © Photo by Jennifer Seavey

That sea levels are rising is hardly new news–they have been doing so since the end of the last major glaciation some 18,000 years ago. The current rate of rise, a little more than a tenth of an inch per year, is also not that unusual–6,000–8,000 years ago the seas were often rising 10 times faster. What is different today and the reason for concern is that back then in response to rapidly rising waters, coastal dwelling Floridians just picked up and moved uphill, leaving their villages, burrows, nests and rooted parents behind. Today it is not so easy to move uphill, for humans nor the rest of the biota, but move we must.

The effects of sea level rise are often difficult to differentiate from the myriad of other drivers of coastal change, but the expanses of dead trees looming over Gulf Coast marshes is compelling evidence. The story unfolds very clearly in Yankeetown’s Withlacoochee Gulf Preserve (www.withlacoocheegulfpreserve.com) where saltwater intrusion due to over pumping from the aquifer is not the confounding factor that it is near large cities. The comparatively small tidal fluxes in the Gulf also help in differentiation of the signal of sea level rise from the noise of tides. Another advantage of the Yankeetown marshes and coastal forests is that they are perched atop a stable limestone platform and not on subsiding mucks like in the Mississippi Delta. Finally, as a study site or the destination for an outing, Withlacoochee Gulf Preserve is startlingly beautiful.

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Researchers tag record number of endangered sawfish

April 24th, 2012

By Danielle Torrent

Sawfish saw

After catching small-toothed sawfish, researchers tie the rostrum with a rope to help hold the fish while tagging it. © Photo by Jim Wilcox

Scientists studying marine animals at the Florida Museum of Natural History seem to be living the high life, heading to the coast for fishing trips in the name of research.

But when you take away the refreshments, the relaxation most people associate with going fishing and consider they’re looking for one of the most rare and dangerous animals in Florida’s waters, being on a boat takes on a new meaning.

Tasked with developing a conservation plan for the federally endangered small-toothed sawfish, researchers have been attempting to track their movement patterns since 2010. But until their last trip in late March that resulted in eight tagged individuals, they had only hooked a few of the massive creatures in the Florida Bay.

“I was pretty surprised, I mean we caught one a day, and on two days, we caught two a day,” said marine biologist Yannis Papastamatiou, who is responsible for placing tracking devices on the animals. “And on one of those days, we caught two at exactly the same time.”

The crew is often accompanied by George Burgess, director of the Florida Program for Shark Research at the Florida Museum, but Burgess spent this trip nursing sawfish wounds inflicted during a previous excursion in Florida Bay.

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Museum researchers unlock genetic data of recently rediscovered "hidden" native Florida plant

March 1st, 2012

By Danielle Torrent

Matthew Gitzendanner

Florida Museum researcher Matthew Gitzendanner displays the holotype specimen of Ziziphus celata, endemic to central Florida. © Photo by Jeff Gage

In 1947, a small package containing an unknown plant specimen arrived at the Florida Museum of Natural History Herbarium. For 37 years, the thorny stem and leaves sat pressed between pages of a yellowed newspaper, filed in a cabinet among the vast library of Florida plants, until University of Florida botanist Walter Judd encountered the specimen in 1984. Knowing it was from the Lake Wales Ridge in central Florida, Judd and herbarium curator David Hall traveled to the area in search of wild populations, but returned to Gainesville empty-handed. Pronouncing it extinct, they published a paper naming the mysterious plant Ziziphus celata.

“Celata means hidden, because the plant was hiding from us,” Judd said. “We searched every little scrub patch that we found, but we didn’t see it – we were hoping that this would kind of be like the pebble that gets the avalanche rolling, and soon enough, there was an article written about the plant in the local newspaper.”

The media attention attracted amateur botanists and collectors to the field, and three years later, native populations of Ziziphus celata were re-discovered. But the excitement was short-lived, as researchers soon learned the species was self-incompatible, meaning two different plants are needed to produce seeds.

In 2007, the tide turned again when additional populations were found, and recent research on the plants revealed they have some genetic diversity, giving new hope to the 15-year effort to re-establish one of the state’s most rare and endangered plants.

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