Studying bursts of diversification in tropical bats

Sharlene Santana holds a Lophostoma silvicolum bat.

Sharlene Santana is an evolutionary biologist and the new curator of mammals here at the Burke Museum. She studies how behavior, diet, anatomy and function result in bursts of diversification in tropical bats – mostly from Panama, Costa Rica and Venezuela.

Sharlene was born and spent most of her life in Venezuela. Growing up in the tropics fostered her love for animals and interest in their diversity.

Some of the tropical forests where Sharlene has worked no longer exist because they have been cut down. While Sharlene releases most of the bats she studies in the field, she collects some specimens to help preserve the biodiversity of these increasingly threatened habitats. In her research today and other studies in the future, these specimens in collections will help answer questions that haven’t even been asked.

I recently sat down with Sharlene to ask her why and how she studies bats.

Cloudy with a chance of horned lizards

Many people go to Mexico for a relaxing beach vacation. But Burke scientists spent their "summer vacation" searching the desert for signs of the elusive horned lizard.

Horned lizards are especially diverse, including sixteen species that vary dramatically from each other (picture Thanksgiving dinner, when you're wondering how that crazy cousin could POSSIBLY be related to you).

Some give live birth like humans, while others lay eggs. Some can squirt blood out of their eye as a defense mechanism against predators, while others can’t. Not to mention, horn and tail lengths vary dramatically between the species. How, where, and why did these lizards adapt so differently from one another?

Piecing together Patagonia's ancient vegetation

Fossil site in Patagonia, Argentina.

Most people hardly notice what's on the ground beneath their feet. But to researchers like Regan Dunn, a graduate student studying paleobotany at the University of Washington, fallen leaves provide invaluable clues to understanding how climate change impacted life on earth - and how our actions today will shape the future.

Regan is part of a team led by Caroline Strömberg, Burke Curator of Paleobotany, that is studying 40 to 18 million-year-old plant and animal fossils found in Patagonia, Argentina. “This was a time with major climate change and some extinction events, so we really want to understand how vegetation was affected by these changes.”

To understand the impact of climate change on Patagonia’s vegetation, they set out to reconstruct what types of vegetation existed in ancient Patagonia. To collect data, Regan visited Costa Rica - which has a modern climate similar to that of ancient Patagonia.

The Sahara Before Dinosaurs

Located in the Burke Museum’s lobby, a display currently case holds some important research conducted by Burke vertebrate paleontology curator Dr. Christian Sidor. Specifically, The Sahara before Dinosaurs mini-exhibit displays the objects and research collected by Sidor during expeditions to northern Niger. Research is connected to both science and culture, so the display highlights fieldwork, lab work, and the broader impact of research findings on the public.

During these expeditions, Sidor has been studying the Late Permian period (240—250 million years ago), before dinosaurs roamed the earth. Northern Niger has been the location of his trips because he is specifically examining which plants and animals lived near the equator during this period of time.

Based on information found in the fossils collected, Sidor and his research colleagues concluded that the supercontinent Pangea that existed during the Permian period had a desert-like center. Because of this climatic barrier, the animals in Niger were isolated from the rest of Pangea.

The Sahara before Dinosaurs display will be on view until October 3rd. Come see the display for yourself and view collections that include fossilized remains of Permian reptiles and a giant amphibian!

Posted By: Andrea Barber, Communications

Photos: (Top) The Sahara Before Dinosaurs display case in the Burke Museum lobby; (bottom)Pangea drawing courtesy of USGS

How old are dinosaurs? Older than we thought!

Here’s some breaking news: dinosaurs may have lived much earlier than previously thought!

Burke Museum curator of vertebrate paleontology Christian Sidor and a team of paleontologists recently discovered that a dinosaur-like creature called Asilisaurus kongwe lived as many as 10 million years earlier than the oldest known dinosaurs.

Asilisaurus is part of a sister group to dinosaurs known as silesaurs. Silesaurs are considered dinosaur-like because they share many dinosaur characteristics but still lack key characteristics all dinosaurs share. The relationship between silesaurs and dinosaurs is analogous to the close relationship of humans and chimpanzees. Sidor and his colleagues concluded that dinosaurs might also have lived at the time of Asilisaurus – bumping back the age of the oldest dinosaurs by 10 million years.

The Asilisaurus fossil bones were recovered from a single bone bed in southern Tanzania, making it possible to reconstruct a nearly entire skeleton. The creature would have stood about 1.5 to 3 feet tall and 3 to 10 feet long, weighing between 22 to 66 pounds. The description of the new species appeared in a paper published March 4 in Nature. The lead author is Sterling Nesbitt, at The University of Texas. Sidor is among the co-authors.

An article in the University Week gives more detail about the new species. Christian Sidor was also recently featured on NPR’s Science Friday, in an interview about the discovery. Click here to listen to his interview.

Posted by: MaryAnn Barron Wagner, Communications

Photos: (center) A life recreation of Asilisaurus kongwe. Marlene Hill Donnelly, Field Museum; (right) Christian Sidor excavates a fossil from the Manda beds in Tanzana in 2007, photo by L. Tsuji.

Inexpensive, Educational and Fun!

Posted by: Karin Hoffman, Communications

Looking for something to do tonight? Come to the Burke Museum and listen to local photographer Paul Bannick talk about the adventures behind his amazing wildlife photos featured in his book The Owl and the Woodpecker: Encounters with North America’s Most Iconic Birds. Starting at 7 pm tonight Bannick will share some of the fascinating stories behind collecting these photographs, many of which were captured while kayaking, snowshoeing or hiking around the Pacific Northwest. Tickets are still available - $5 at the door and FREE for Burke members!

If your dance card is full for tonight, then check out the second lecture offered in our Lucy Talks series tomorrow night at Pacific Science Center (Eames Auditorium.) Dr. Katherine Taylor, a forensic anthropologist with the King County Medical Examiner Office, will present “Looking Through Time: How modern methods are shedding new light on old bones.” Dr. Taylor will discuss how advancements in the science of forensic anthropology inform the study of ancient hominids. Tickets are $5 at the door and FREE for Burke members!

Photo by Paul Bannick, The Owl and the Woodpecker: Encounters with North America’s Most Iconic Birds.

Cruisin' the Fossil Freeway

Posted by: Rebecca Durkin

What do you get when you take one Seattle-born paleontologist, add one wacky Northwest artist, stick ‘em in a pick-up truck, and set them off on an adventure? Cruisin’ the Fossil Freeway, the new book by Kirk Johnson and Ray Troll, takes us on an “epoch” journey across the western states at 65 mph in search of fossils.

The hilarious duo will be reading from their new book and signing copies at the Burke tonight at 7 pm – tickets are $5 at the door and free to members.

Want a taste of what you’re in for? Check out their brief interview on NPR’s All Things Considered, discussing “Jurassic Pork” and “PNS” (Paleo Nerd Syndrome). Then join us tonight for the real scoop!

- Rebecca

The Hunger

Posted by: Karyn Gregory

In a tale that sounds like it came from a grade B scifi/horror film, comes this gem about radiation-eating fungi:

"Since the 1986 meltdown, at the Chernobyl Atomic Energy Station, the numbers of 'black fungi', rich in melanin, have risen steeply. [Researcher] Casadevall speculated that the fungi could be feeding on the radiation that contaminates the ruin of the nuclear reactor."

Essentially, the mold uses melanin (yes, the same melanin found in human skin pigment) to transform radiation into energy. The implications of this discovery are staggering. Not only could this hold the key for an alternative energy source, but the fungus may also be the answer for tackling nuclear waste.

Wow!

-Karyn

(via apostropher)

This week in natural history...

Posted by: Rebecca Durkin

Climate change shaping evolution?
Researchers predict that as winters continue to warm, sheep bodies will get smaller
A team of researchers has linked changes in shape and size trends in Scottish sheep populations to the influence of climate change. Analyzing twenty years of data, the researchers were able to demonstrate the connection – harsh winter weather favors larger bodies, but as average winter weather warmed over recent years, there is less selection for the once favorable larger bodies. “People have argued for a long time that climate change is leaving an ecological legacy, but we have shown it will leave an evolutionary legacy too,” researcher Tim Coulson told the BBC.

Digging up digging dinos
The first definitive evidence of burrowing dinosaurs was discovered in Montana, unearthed from a chamber at the end of a tunnel. The dinosaur, named Oryctodromeus cubicularis, meaning "digging runner of the lair," was built for digging with a snout, shoulder girdle, and pelvis morphologically similar to those of burrowing animals. Researchers suggest that the burrowing lifestyle of the small, 95 million-year-old specimens provided shelter, a place to rear young, and possible protection from environmental extremes.

American Crocodile no longer endangered
On Tuesday, the once “endangered” American crocodile was downgraded to a “threatened” status by the U.S. Fish and Wildlife Service. The species is still protected by the Endangered Species Act, but the new classification implies a positive trend in its population recovery. Under its protected status and the preservation of South Florida habitat, the species has gone from an estimated population of 300 in 1976 to up to 2000 today. The American crocodile remains endangered in Central and South America.

- Rebecca

The Darwin Diaries

Posted by: Rebecca Durkin

The diaries of Emma Darwin, wife of Charles Darwin – the “father” of evolutionary theory – have been made available online for the first time ever. Previously restricted to a select handful of researchers through Cambridge University, the diaries are now publicly accessible to all who are interested in the minutiae of the Darwin family’s appointments, visitors, travel plans, and health developments.

To be clear, the diaries are not narratives of life in the Darwin house. But the diaries do reveal over six decades of the every day humanity of a larger-than-life historic figure. The diaries are also an interesting read for a glimpse into daily life from the female perspective of a middle-class Victorian family.

If Emma’s notes titillate your interest in the Darwin legacy, you can find the complete publications of Darwin, as well as many handwritten manuscripts, available online at the same resource.

- Rebecca

This week in natural history

Posted by: Rebecca Durkin


Split-level Dino – A Texas researcher proposed this week that 125 million years ago, a feathered dinosaur known as Microraptor gui may actually have had an upper and lower set of split-level wings, just like the Wright Bros. biplane (as opposed to tandem wings, like a dragonfly). And though it worked for the Wright Bros., it looks like the biplane approach was likely an evolutionary dead-end in the dino world.

Mega-‘roos – It wasn’t the climate, it was us. According to new research that examined ancient fossil and climate evidence in Australia, the mass extinction of Australia’s mega-mammals can be pinned primarily on humans. The next question, of course, is "How did we do it?” Changing the ecosystems? Over-predation? The research continues.

The Shire Reopens – Researchers who discovered a potential new hominin species, delightfully referred to as a “hobbit” because of its diminutive size, have finally been granted permission to dig around in an Indonesian cave-site in search of other hobbits. With a renewed start, the scientists are hoping to determine whether the hobbit truly is a unique species, how it lived, what it was like, and how it fits into the pattern of human evolution.

- Rebecca