While it is widely accepted that songbirds originated from the Australian continent, how and when they diversified and colonized the rest of the globe has remained a mystery.
Researchers from the University of Kansas, Louisiana State University and three other institutions reconstructed the evolutionary history of songbirds using thousands of DNA sequences from majority songbird lineages and information from the fossil record to provide answers to these questions. They found that songbirds began diversifying about 33 million years ago and underwent extensive diversification in Australia. Furthermore, the researchers also found that songbirds first dispersed out of Australia about 23 million years ago through early islands in the Indonesian archipelago into Asia and subsequently the entire globe.
This new research will be published in Nature Communications on Aug. 30.
“One of the challenges with deciphering songbird evolutionary history is that they diversified so rapidly that previous studies had a difficult time estimating the branching pattern of the songbird family tree,” said lead author Rob Moyle, KU professor of ecology and evolutionary biology and curator of ornithology at the KU Biodiversity Institute. “With advances in DNA sequencing technology, we were able to collect an unprecedented amount of DNA sequence data that helped clarify songbird relationships.”
Songbirds comprise the largest group of birds, with about 5,000 species, accounting for nearly half of avian diversity. They are found on almost all corners of the globe, with the exception of Antarctica, and include the familiar crows and sparrows, as well as elaborate singers like mockingbirds and lyrebirds.
With a better understanding of the songbird family tree, Moyle and his colleagues were able to infer the colonization history undertaken by songbird ancestors.
The dispersal of songbirds from Australia through Indonesia, Moyle said, seems like an obvious explanation to anyone who knows world geography; but one has to bear in mind that tens of millions of years ago, world geography looked a lot different because of the Earth’s constant process of plate tectonic movements.
“Thirty-three million years ago, Australia was thousands of kilometers away from any continent, and New Guinea barely existed,” Moyle said.
Another issue confounding our understanding of songbird evolution is the estimated age of the group, said co-lead author Carl Oliveros, a postdoctoral researcher at Louisiana State University.
“Our estimate for the age of songbirds is about half of most previous estimates, placing songbird evolution in a very different geological landscape than previously thought,” said Oliveros, who earned his doctorate in ecology and evolutionary biology at KU.
“Thus the previous hypothesis of long-distance dispersal by songbirds from Australia to Africa via Indian Ocean landmasses are put into question because these Indian Ocean islands were submerged by the time we think songbirds diversified.”
Oliveros’ and his colleagues’ work also provides an alternative explanation to the high diversity of songbirds that are presently found only in New Guinea. Previous research suggested that songbirds diversified extensively in proto-islands of New Guinea before colonizing adjacent areas.
However, Oliveros and his colleagues believe that songbirds underwent extensive diversification in Australia and subsequently colonized New Guinea after the formation of the New Guinea landmass. They suggest that the aridification of Australia caused the extinction of forest-adapted songbird lineages in the continent, which left relicts of the first colonizers as sole surviving lineages in New Guinea. According to the researchers, this idea is supported by the presence of fossils in Australia of plants and mammals that are currently only found in New Guinea.
The study used tissue samples of birds deposited at the KU Biodiversity Institute collected from expeditions to 25 countries within the past 25 years. This research is supported by funds from the National Science Foundation, KU and Louisiana State.
By Brendan Lynch
Photo: This yellow-breasted satinbird (Loboparadisea sericea) is among the songbirds research shows first dispersed out of Australia about 23 million years ago through early islands in the Indonesian archipelago into Asia and subsequently the entire globe. Image credit: Brett Benz, American Museum of Natural History
Michael Engel, senior curator of entomology, was interviewed for the National Science Foundation’s Science360 radio, which features podcasts and radio programs related to NSF funded research. You can listen on your phone via the 360 app, or go to the link below and scroll down slightly to the “Big Picture Science” icon and listen. The interview is about research Michael has authored on how insects construct camouflage out of sand, plant material and even other insects. To find it, search for Michael Engel at Science360.
If you stroll the halls of a natural history museum anywhere in the world and come face-to-face with the prehistoric fossil of a pterodactyl or mosasaur, the odds are good it was unearthed in Kansas.
Indeed, American paleontology came of age in the 19th century largely thanks to Kansas’ chalky earth — made famous by the University of Kansas’ “Rock Chalk Chant.” The fine-grained chalk, especially good at preserving fossils, was ocean floor during the Late Cretaceous, from 65 to 100 million years ago, when much of Kansas was beneath the Western Interior Seaway.
“That ocean ran all the way from present-day Gulf of Mexico to northern Canada, through the middle part of this country,” said Bruce Lieberman, senior curator at the KU Natural History Museum, which houses one of the world’s foremost collections of Late Cretaceous fossils. “The water would have been warm and tropical, no deeper than 200 meters at its deepest point.”
The KU researcher said the seaway and its shoreline abounded with ancient marine life such as diving birds, winged and swimming reptiles, fish, clams, and ancient squid relatives called ammonites.
“It’d have been a great place to swim, except there were giant mosasaurs and sharks that would have loved to eat a human,” Lieberman said.
While many fossil treasures from the Western Interior Seaway adorn museums, today many thousands more are stored in the back rooms of various research institutions, inaccessible to most people.
So Lieberman is heading up a project to change that. He’s the primary investigator on a new $2.1 million National Science Foundation grant to digitize Western Interior Seaway collections from eight leading institutions — KU’s Biodiversity Institute, the American Museum of Natural History, the Sternberg Museum of Natural History at Fort Hays State University, the South Dakota School of Mines and Technology, the University of Colorado Museum of Natural History, the University of New Mexico, the Jackson School Museum of Earth History at the University of Texas and the Yale University Peabody Museum of Natural History. Scientists from the Paleontological Research Institution in Ithaca, New York will also be involved.
“We have all kinds of fossils in these museums, but too many are buried away in drawers and cabinets that make them inaccessible to scientists and the public,” said Lieberman. “We think digitization of these fossils has value for answering scientific questions.”
For instance, a warming climate during the Late Cretaceous is similar to conditions climate scientists expected Earth to undergo in coming centuries. So the comprehensive view offered by digitizing Late Cretaceous fossils could forecast how species may react to altered habitats.
“We’re going to use computer mapping called ‘ecological niche modeling’ to look at how species were competing with one another — when you pack more species in more tightly, theoretically they’re going to be competing more with each other, which could drive more extinctions,” said Lieberman. “We’d like to see how species adjust their range. Do they partition their range to avoid overlapping as much as possible? This has practical applications because people get food from oceans. We’re predicting as climate gets warmer it’ll cause lots of extinctions. But we’re wondering if we should expect increased competition as well.”
Not only will the digitization work make the Western Interior Seaway fossils more useful to scientists, but the grant will open up access to the fossil treasures for the public at large.
“We’re going to be creating images and providing information about where fossils come from,” Lieberman said. “The public can look at the same resources as a museum researcher, to expand science out to the public more.”
The public outreach will center on a new “Digital Encyclopedia of Ancient Life” intended as an open-access textbook of paleontology. The atlas will feature an online Cretaceous Atlas with at least 800 species from the Western Interior Seaway to be added to the existing Digital Atlas of Ancient Life for the web and an iPhone app.
In addition to open-access resources, the researchers will develop K-12 curricular materials from the digitization project as well as providing 3-D scans of the fossils and 3-D models for some classrooms. Additionally, exhibitions based on the grant work are planned at the associated institutions.
Lieberman said the work would involve at least 13 undergraduates and 4 graduate students with the intention of recruiting students from underrepresented groups.
Along with Lieberman, KU Biodiversity Institute faculty working on the grant include Chris Beard and Jim Beach.
Indeed, KU has been at the forefront of digitizing fossils in the 21st century — in the same way that Kansas, thanks to its chalk, was the hotbed of paleontological fieldwork in the 19th century.
“I’ve always thought it was cool that our KU ‘Rock Chalk Chant’ ultimately goes back to rocks in Kansas where some of these awesome fossils were discovered,” said Lieberman. “When people today are chanting ‘Rock Chalk’ they’re probably not thinking of these fossils — but when I hear the chant, I think of fossils.”
By Brendan Lynch
Photo credits: 1—Richard T. Bryant; 2—Laura Mohr of the KU Biodiversity Institute; 3—Jonathan Hendricks of the Paleontological Research Institution
Sarah Z. Gibson, graduate student, has received the Albert Wood Student Research award at the 76th Annual Society of Vertebrate Paleontology meeting, held this year in Salt Lake City, Utah. The purpose of this award, named in honor of Dr. Albert E. Wood, is to support student research that involves museum and university vertebrate fossil and/or natural history collections. Recipients of the award conduct collection-based scientific work on some aspect of vertebrate evolution, with special attention given to proposals that greatly enhance the value of fossil material already residing in museum collections.
Sarah is currently a Doctoral Candidate at the University of Kansas, under the guidance of Dr. Hans-Peter Schultze. Sarah studies the evolutionary relationships of ray-finned fishes from the Triassic of North America. Sarah will use the award to visit the fossil collections of the Academy of Natural Sciences in Philadelphia, Pennsylvania, where she will examine the extensive collection of fossil fishes from the Triassic and Jurassic of New England.
Leonard Krishtalka, the Biodiversity Institute director, has been elected as a Vice Chair of the Governing Board of the Global Biodiversity Information Facility (GBIF) at its annual meeting in Brazil in October. GBIF is an intergovernmental body headquartered in Copenhagen that provides free and open access to the data on the animals and plants of the planet for science and society. Krishtalka was also re-elected to the Board of Trustees of the JRS Biodiversity Foundation, which funds research on African biodiversity and its conservation, particularly pollinators and freshwater animals and plants.
A $100,000 grant from the David B. Jones Foundation will help to develop a new generation of paleontologists at the University of Kansas, enabling students to pursue fieldwork in locations such as Wyoming and Turkey aimed at solving some of evolution’s deepest mysteries.
“This money can be used flexibly and broadly to support research training and educational outreach relating mainly to graduate and some undergraduate students at KU in vertebrate paleontology,” said K. Christopher Beard, Distinguished Foundation Professor, Department of Ecology & Evolutionary Biology and senior curator at the KU Biodiversity Institute, who is heading up work under the new grant.
Beard’s research focuses on the early evolution of mammals, including primates. He said the first three David B. Jones Fellows in Vertebrate Paleontology — Matt Jones, Spencer Mattingly and Ryan Ridder — would begin training this spring.
“It’s often hard to get federal funding to support participation by graduate and undergraduate researchers, especially in my kind of research, which is field-based,” Beard said. “Costs can escalate, especially with international fieldwork, airfare and procurements beyond lodging and food — it really can skyrocket. But in paleontology, one of the most important components is to get students access to work in the field.”
The researcher said that student work and training would center on two locations: Wyoming and the nation of Turkey.
In Turkey, Beard’s students will have the opportunity to piece together the ancient migration of mammals in the geographically unique Pontide region, which researchers believe 45 million years ago was an island treasure house of biodiversity, something like today’s Madagascar.
“We’re trying to determine if the Pontide terrain played a role in how animals were able to move back and forth between Asia and Africa, close to the appearance of anthropoid primates,” Beard said. “The more fossils we collected there, the weirder they got. This Pontide island had a unique fauna never found anywhere else but a couple of animals that clearly came from Africa. The most common mammals we’ve found there are primitive hoofed mammals, clearly related to animals common in western Europe, but millions of years earlier — and we’ve got a bat that seems related to Asia.”
In terms of migration of these animals, Beard sees the ancient Pontide region less as a stepping stone between Asia and Africa and more of a “cul-de-sac.”
“Animals were getting to the islands, but not leaving so much — they seemed to get stuck there,” he said.
Before undertaking fieldwork in Turkey, the David B. Jones Fellows will travel to Wyoming to conduct research to establish how mammals during the late Paleocene responded to a warming climate.
“We’re using Wyoming fieldwork as a proving ground to give students experience in somewhat exotic but not crazy-exotic setting before we take them internationally,” Beard said. “In the southwestern part of the state, we’re establishing a record of how mammals evolved in response to climatic change in the Paleocene, right after the dinosaurs have died and mammals are beginning to evolve rapidly, and comparing that to other findings from the Bighorn Basin.”
Beard said his students would be surveying for fossils, excavating sites and screen-washing sediment for minuscule fossils, as well as partnering with geologists to learn to read the landscape.
“They’ll pick up how to interpret sedimentary rocks, to understand what the ancient environment would have been,” he said. “Are you looking at ancient marsh, lake, seashore or river floodplain? Those are basic skills associated with areas like sedimentology and stratigraphy.”
In addition to work in the field domestically and internationally, the David B. Jones Fellows studying with Beard will be trained in the full “assembly line” of paleontological research, including restoration of fossils, and learning how to mold and cast fossil specimens. The training will be carried out under guidance from David Burnham, preparator at KU’s Natural History Museum. Further, with KU’s Oscar Sanisidro, the fellows will learn techniques of scientific illustration.
A key goal of the grant is facilitation of student publishing of findings in peer-reviewed journals.
“We want to stimulate scholarly research on part of the graduate students,” Beard said. “KU paleontology already has a great reputation, but we want to push it to the top of the mountain nationally, and one way is to have graduate students publishing scholarly work and giving presentations at conferences. In this grant, there’s funding to support that as well.”
Additionally, the grant provides funds for KU paleontology students to receive training in pedagogy.
“It’s something I faced as a graduate student,” Beard said. “I wound up learning a lot about research, but nobody taught me anything about how to teach. Skills in basic pedagogy are too often lacking in an overall graduate curriculum.”
Finally, the students will develop and lead outreach programs and events at KU’s Natural History Museum to engage the public and young people. Public outreach is a key goal of the David B. Jones Foundation, with its mission to further “educational, research and charitable activities working in the science of paleontology who primarily promote those activities within the United States of America.”
“David B. Jones was an amateur paleontologist who was involved in using fossils to get kids interested in science in general,” Beard said. “For instance, he was active in the Boy Scouts. I think this lines up so well with the agenda of the foundation.”
By Brendan Lynch
Photos by Gregoire Metais
Andrew Short, associate curator of entomology, has been selected as a 2017-2018 Fulbright Scholar in Brazil. He will be hosted by the National Institute of Amazonian Research (INPA) in Manaus, and will spend approximately 5 months over the next two years there to conduct regional fieldwork, collaborate with their aquatic bioassessment team, and teach graduate student workshops on entomology and biodiversity.
A newly discovered mammal in the Pacific has earned worldwide attention after scientists named it Rattus detentus to call attention to an Australian detainee center on the animal’s home island. Recently, the new animal was featured as a top scientific discovery of 2016 in Discover magazine’s “Year in Science” issue.
For decades, scientists had suspected an unnamed animal was inhabiting Manus Island, part of the Papua New Guinea Admiralty Group.
“Its bones and teeth were known for quite some time,” said Robert Timm, professor in the Department of Ecology & Evolutionary Biology and curator emeritus in the Biodiversity Institute at the University of Kansas. “For thousands of years, indigenous people on that island would eat them, and we know that because of middens — discarded trash from people’s kitchens. So we had lots of older fragmentary remains but no modern specimens. We knew of its existence because of skeletal remnants from only one rock shelter."
That all changed recently when biologists working with Conservation International and a graduate student from Finland, conducting research for his dissertation on Manus Island, located the first contemporary example of the rare rodent.
“Local residents on the island continue to set traps to capture these rats and other wildlife for food,” Timm said. “We now have three modern specimens. The first two consist of discarded bones from meals and were salvaged in 2002.”
In 2012, the graduate student obtained a fresh specimen that was captured in a snare by a local boy working with him.
“Now, we have a beautiful specimen to work with and well-preserved DNA,” Timm said. “The DNA is critical in ascertaining where this species belongs in the tree of life.”
Although the rodent’s relationship to other species is now understood, Timm said the habits and abundance of Rattus detentus remain shrouded in mystery.
“We actually know almost nothing about its behavior because it’s so hard to find,” he said. “We believe it specializes on eating big seeds that are hard to chew into, because of the teeth. One of our Australian colleagues worked very hard to find more of this newly recognized species using camera traps and a variety of other techniques, and he didn’t find any evidence of them whatsoever. That suggests there aren’t very many of them left.”
Manus Island is now best known for the Manus Regional Processing Center, an immigration detention facility operated by the government of Australia. The facility has drawn the ire of human rights groups throughout the world.
So Timm, KU research associate Ronald Pine and co-authors named the new rodent Rattus detentus to bring more attention to the refugee center.
The word detentus is Latin for “detained” and is meant to indicate the isolation of this animal on Manus Island and the recent use of the island to detain people seeking political or economic asylum. (Last August, Australia announced its intention to close the center, although a timetable for closure remains unclear.)
In addition to humanitarian concerns, Timm said the sprawling center contributes to a deteriorating habitat for the newly discovered species. Further threats include other wildlife, along with the introduction of domestic cats on Manus Island and widespread logging.
“There is significant deforestation there and no replanting of these beautiful tropical forests,” said the KU researcher. “Some sections of it are still wonderful, with high trees, thick luxurious growth — lots of habitat for all sorts of plants and animals. The problem is that now there are too many people and not enough care taken of the habitat.”
By Brendan Lynch
Photograph courtesy of the Journal of Mammalogy and Valter Weijola.
Desui Miao, collection manager of vertebrate paleontology, and his colleagues, Feixian Wu, Mee-mann Chang, Gongle Shi, and Ning Wang have been published in Scientific Reports with an article titled, "Fossil Climbing Perch and Associated Plant Megafossils Indicate a Warm and Wet Central Tibet During the Late Oligocene." Their article provides a report on fossil biota with new insight on the Tibetan Plateau’s palaeogeography and palaeoenvironmemt, crucial information for understanding Asia’s climatic history. Miao and his co-authors' findings indicate a warm and humid environment in Tibet's past, which conflicts with previous reports of a “high and dry Tibet.” This research prompts re-evaluation of previous knowledge on this subject. Read the article here.
William Duellman, curator emeritus, has been featured in National Geographic news for his herpetology research. Liz Langley referenced Duellman’s book Marsupial Frogs in her article, “5 Animals That Carry Babies On Their Backs,” noting the unique ways some frogs from the South and Central American regions lay their eggs. As explained in Duellman’s book, some frogs, such as the horned marsupial frog, lay their eggs in a pouch located under the skin on the mother’s back as the tissue of the pouch allows for vital nutrients to get through to the eggs. Read more here.
Photo by Joel Sartore