Fossils link Caribbean bat extinction to humans, not climate change

February 11th, 2015
Soto-Centeno with bat skull

Study co-author J. Angel Soto-Centeno displays the fossilized skull of a Cuban fruit bat, Brachyphylla nana.
Photo courtesy of J. Angel Soto-Centeno

By Stephenie Livingston

Sharing caves with millions of bats, the Caribbean’s first humans may have driven some species of the winged mammals to extinction.

“Scientists have been studying bat fossils in the Caribbean for years,” said David Steadman, curator of ornithology at the Florida Museum of Natural History. “The problem is, no one knew how old the fossils they were studying actually were.”

Bats have dominated the Caribbean for millennia, once sharing the islands with at least 73 species of mammals, such as primates, rodents and sloths. But following an ancient event called the Last Glacial Maximum, sea levels rose enormously, islands became smaller, and it is thought that most of the Caribbean’s land mammals became extinct.

New radiocarbon dates show that bats continued to thrive until (more…)

Island isolation, warming climate shapes Mediterranean Basin evolution

January 14th, 2015
Mediterranean Basin

Taken on the island of Crete, this photograph shows the typical habitat of bellflowers.
Florida Museum of Natural History photo by Andrew Crowl

By Stephenie Livingston

From the jungles of Southeast Asia to the Greek Islands, Florida Museum of Natural History botanist Nico Cellinese has searched for the answers to how evolution works. But during fieldwork in the Mediterranean Basin—a biodiversity hotspot—she found more questions than answers.

“There are so many islands and so many island endemic species in the basin that it makes you wonder what is going on in this place to make it so highly dynamic,” said Cellinese, associate curator of the Florida Museum Herbarium and Informatics. “It’s a very peculiar place. It’s the kind of place you just have to dive into, and not stop until you figure something out.”

Cellinese received a National Science Foundation $865,000 Early Faculty Development Career Program Award in 2010 to investigate the basin’s rich biodiversity and better understand why certain species only occur there. The grant has supported Cellinese’s research on genetic diversity in the flowering plant group Campanulaceae, also known as the bellflower family—a model group for studying the influences of geological activity, climate change and human pressure on island evolution and endemism.

The five-year award has resulted in the study of nearly 1,000 species of bellflowers worldwide, focusing on those restricted to islands in the Mediterranean Basin. The research adds to the work of Charles Darwin and (more…)

Study reveals 180 million years of parasitic infestation in crustaceans

October 8th, 2014
modern isopod-infested decapods

These modern isopod-infested decapods from the Philippines show prominent swellings caused by parasites on the right side.
Photo courtesy of Klompmaker et al. (2014) in PLOS ONE

By Stephenie Livingston

When Darwin suggested the “survival of the fittest” concept, he did not necessarily mean “survival of the biggest.”

The large marine animals of the past, like prehistoric mega-sharks and whales, draw popular attention and the interest of researchers alike. However, the smaller invertebrate animals dominated Earth in the past and still do today.

Florida Museum of Natural History post-doctoral researcher Adiel Klompmaker’s passion lies in studying the small creatures of the deep. It was while collecting specimens of crustaceans at a fossil reef in northern Spain that he noticed a strange swelling on a fossilized crab.

“What is this? Was it sick? Is this a disease of some kind?” wondered Klompmaker. “I had never observed these swellings in the field.”

The culprit was a parasitic isopod crustacean no more than 16 millimeters in size.

The parasitic isopod causes a swelling (Kanthyloma crusta) so noticeable that it survives in the fossil record, though the traces of these “passengers” have not been thoroughly explored until now, Klompmaker said. The isopod parasites latch onto the inner shell of a crustacean, feeding on it and (more…)

Museum researchers advance ‘DNA revolution,’ tell butterflies’ evolutionary history

September 11th, 2014
Kawahara

Assistant curator of Lepidoptera Akito Kawahara led a yearlong study that revealed monumental discoveries about the evolutionary history of butterflies and moths.
Florida Museum of Natural History photo by Kristen Grace

By Stephenie Livingston

The wispy, delicate nature of butterflies and moths is part of their charm, but their soft bodies do not preserve well in the fossil record, posing a problem for scientists since the early history of Lepidoptera research. Now, by tracing nearly 3,000 genes to the earliest common ancestor of butterflies and moths, Florida Museum of Natural History scientists have created an extensive “Tree of Lepidoptera” in the first study to use large-scale, next-generation DNA sequencing.

Among the study’s more surprising findings: Butterflies are more closely related to small moths than to large ones, which completely changes scientists’ understanding of how butterflies evolved. The study also found that some insects once classified as moths are actually butterflies, increasing the number of butterfly species.

“This project advances biodiversity research by providing an evolutionary foundation for a very diverse group of insects, with nearly 160,000 described species,” said Akito Kawahara, lead author and (more…)

Scientists rewrite evolutionary history of tiny sea cucumbers

July 14th, 2014
Phyrella mookiei

This close-up of the holotype specimen of Phyrella mookiei shows the arrangement of the tentacles and mouth.
Florida Museum of Natural History photo by François Michonneau

By Stephenie Livingston

Scientists at the Florida Museum of Natural History have discovered that a group of tiny sea cucumbers has enormous taxonomic problems.

The use of DNA analyses in taxonomic research has increased in recent years, making it possible for scientists to better understand poorly known species and build knowledge of Earth’s more obscure biodiversity. This type of work is exemplified by the research of François Michonneau, a former invertebrate zoology Ph.D. student with the Florida Museum, who studies the oceans’ most diverse order of sea cucumbers, Dendrochirotida, which includes many small species—most only a few centimeters in length. Studying Phyrella, a genus of Dendrochirotida, Michonneau found that several species of sea cucumbers may be assigned inaccurately within the order.

“The systematics of sea cucumbers is messy and full of inaccuracies,” Michonneau said. “Our revision is just touching the tip of the iceberg as far as cleaning up the confused state of taxonomy in the order Dendrochirotida. The purpose of our study is to identify the appropriate traits to classify sea cucumbers at the genus and (more…)

Museum program inspires teachers to seek new horizons in science

February 14th, 2014
California secondary school science teachers Chris Carlson and Laura Beach view marine malacology specimens in Dickinson Hall. Florida Museum photo by Jeff Gage

California secondary school science teachers Chris Carlson and Laura Beach view marine malacology specimens in Dickinson Hall.
Florida Museum photo by Jeff Gage

By Stephenie Livingston

From a fossil museum curated by students to a garden used for experimentation, an innovative program that exposes educators to scientific fieldwork is significantly impacting classroom curriculum in California and Florida.

The Florida Museum of Natural History’s Panama Canal Projects’ Partnership for International Research and Education program brings scientists and teachers together to engage in the real world of science through inquiry-based curriculum development during a two-week field trip to Panama. California teachers from Santa Cruz and Watsonville were joined this year by (more…)

New Museum study suggests seashell loss due to tourism may have global impact

January 16th, 2014

By Stephenie Livingston

These Donax trueloides shells from the Florida Museum collections are the same type of seashells found on the Mediterranean coast of Spain where researchers surveyed a small stretch of shoreline. Florida Museum photo by Jeff Gage

These Donax trueloides shells from the Florida Museum collections are the same type of seashells found on the Mediterranean coast of Spain where researchers surveyed a small stretch of shoreline.
Florida Museum photo by Jeff Gage

Tourism may be damaging the very destinations treasured by visitors. Global tourism has increased fourfold over the last 30 years, resulting in human-induced shell loss that may harm natural habitats worldwide, according to Florida Museum of Natural History Thompson Chair of Invertebrate Paleontology Michal Kowalewski.

Appearing in the journal PLOS One on Jan. 8, 2014, the new study by researchers from the Florida Museum on the UF campus and the University of Barcelona demonstrates that increased tourism on the Mediterranean coast of Spain correlated with a 70 percent decrease in mollusk shells during the tourist season in July and August and a 60 percent decrease in other months. Kowalewski, lead author on the study, said scientists fear shell removal could cause significant damage to natural ecosystems and (more…)