Many people are familiar with the Galapagos finches, and the evolutionary theory that differences in beak size led to the groups’ diversification. It’s one of the most popularly cited examples of a process known as adaptive radiation. Now, the frequency of that evolutionary process in nature is being challenged by a group of KU Biodiversity Institute graduate research students.
In a paper to be published in the journal Trends in Ecology and Evolution in January, the students argue why many instances of evolution previously believed to be caused by adaptive radiations are not truly “adaptive” but rather other types of evolutionary radiation altogether, or a blend of several forms.
“We read a lot of papers where something interesting biologically was going on, but it was being mischaracterized as adaptive, when truly there were other processes that were being ignored,” said graduate student Kaylee Herzog, one of the seven students who coauthored the paper.
Evolutionary radiation consists of several ways in which speciation, or the creation of new species from a single common ancestor, occurs. In early studies of evolutionary radiation, adaptive radiation was once thought to be the only way speciation could take place. This theory was proven false, after it became clear that many causes of radiation exist, oftentimes many in the same instance.
The group believes that geographic radiation in the finches could be the actual cause for changes in certain cases, or that both adaptive and geographic radiation play a role in some speciation. Geographic radiation is caused by two groups of the same species being physically separated and exposed to different environments. The high diversity of Galapagos finches is only one of several examples that the students say could be falsely attributed to adaptive radiation.
Graduate student Marianna Simoes says the paper’s concept was first initiated two years ago, when the graduate students began meeting for a macroevolutionary biology course at the University of Kansas. During the course, the students discussed types of radiation such as adaptive, exaptive, geographic, and climatic. While studying these processes, the group decided to make the occurrence of adaptive radiation the focus of their discussion group which followed the course the next semester.
In the discussion group, the students began to dig deeper into inconsistencies they found in the labeling of the processes of evolutionary radiation. The students found instances of possible false attributions to adaptive radiation in each of their specific fields of research, and brought these studies back to the group for discussion. They then teased out what they believe to be the true causes of speciation in these groups. While writing the paper, the students also named the process of pseudoradiation. This is the first time the process, which is related to but distinct from evolutionary radiation, have been summarized in one paper.
“We’ve found that adaptive radiation is not really the trigger for all of these speciations, so that’s where the rest of the different kinds of radiation come in,” graduate student Laura Breitkreuz said.
While the students maintain that adaptive radiation plays a big role in evolutionary radiation, they hope the paper will help point out the importance of recognizing other triggers that often occur.
Imagine shoveling soil to create a backyard garden plot and unearthing a rock embossed with the fossil remnant of a creature you’ve never seen before. It looks like something out of the ocean, but you live in the Midwest.
Is it a rare fossil from hundreds of millions of years ago or just the trash from a previous homeowner 50 years back?
Now, a free app developed at the University of Kansas with support from the National Science Foundation will enable anyone with an iPhone or iPad to discover and classify fossils with the eye of a scientist. The Digital Atlas of Ancient Life is available now at no cost for download from iTunes.
“We’re interested in making our science more accessible to the general public,” said Bruce Lieberman, professor of ecology and evolutionary biology, who is the primary investigator on the NSF grant. “We know people are captivated by paleontology and interested in fossils. The app links to pictures, maps and information about how long ago fossils occurred. We thought, ‘Hey, when people are out finding fossils, they’re not on their computer.’ They might be out walking, pick up a fossil and think, ‘Cool! What species is this? Where have others like this one been found?’”
Lieberman, who also serves as senior curator of invertebrate paleontology at the Biodiversity Institute, said the new app builds on a strong KU legacy of digitizing its collections so they can be of use to people around the world.
“It’s a way for anyone to find species in the field and learn something about them, be they farmers, amateur paleontologists, teachers of earth sciences or biologists,” Lieberman said. “Certainly some professional paleontologists could use it. We wanted to distill scientific information gathered over many years. We might have some scientist in Russia who wants to see fossils in my cabinets, but they don’t have airfare and couldn’t travel to Kansas. Or there might be a rancher in Dodge City with a fossil who can’t drive to Lawrence and see what’s in our collection. Now we can provide the data and allow them to dig outside in the natural environment in Kansas or anywhere, then instantly access pictures and explanations of what fossils they’ve found and what they’re related to.”
The researcher said his team had elementary, middle school and high school teachers in mind when they developed the new app, hoping to give instructors a practical tool for engaging students with the wonders of the natural world.
“For school groups a teacher might be able to say, ‘Hey we’re going on this field trip and we can find these specific fossils in this place,'” Lieberman said. “Outside a WiFi zone, they can show student pictures of fossils and where they occurred. Like with Google Maps, with this app you can zoom down to any geographic scale. A teacher can look at a map of specimens and say, ‘This one was found on Highway 59 near the junction with 458 — and we can go back again and find another one.’”
The Digital Atlas of Ancient Life app focuses on fossils with origins in the Pennsylvanian period, about 290 million years ago, with fossils common to Kansas and the Midwest; the Ordovician period, with fossils often found near Ohio; and the Neogene period with fossils usually located the Southeastern U.S.
Indeed, discovering fossils is easier than many people imagine, Lieberman said.
“The best thing to do is look around a road cut or a little quarry where rocks are exposed so you don’t have to do a lot of digging,” he said. “In Kansas, many of those yellow rocks that you see are packed with fossils — some are 100 percent fossils. Of course, don’t stop along a busy stretch of road or an interstate. But on all other roads, at least in Kansas, as long as you’re cautious, those layers of yellow rock expose fossils at road cuts. You can just bang a fossil out.”
Lieberman’s collaborators on the project include Alycia Stigall at Ohio and Jonathan Hendricks at San Jose State University, along with Jim Beach at KU. Rod Spears, former staffer at the Biodiversity Institute, and his son Zach programmed the app. The researchers have published a scholarly description of the project in the online peer-reviewed journal Palaeontologia Electronica.
But according to Lieberman, the real aim of the work was to provide everyday people a digital tool to connect them to fossils and inspire curiosity about our place in the universe.
“The most fascinating thing to me is to think about how the world was so different before humans were here, to be a thousand miles from the nearest ocean but pick up a shell of a clam that once lived by the side of the seashore,” he said. “It puts human life into perspective to think about so much history and time and change. There’s evidence that fossils have fascinated humans for tens of thousands of years. We’ve found prehistoric encampments with fossils people had brought from hundreds of miles away. We’re intrigued by this connection to place and history, and this app is looking at history at a large scale. It connects us to the world and makes us think, ‘Why are we here, and how did we get here?’”
- Brendan Lynch, KU News
Cori Myers, former student of Bruce S. Lieberman, Division of Invertebrate Paleontology, has been offered a tenure track job at the University of New Mexico in the Department of Earth & Planetary Sciences.
A researcher at the University of Kansas is part of a team to uncover strong evidence of brood-care parenting strategy in 450-million-year-old crustaceans — the oldest verification of ovarian-to-juvenile brood care in the fossil record.
The new species of ostracod exhibiting brood care, which the team named Luprisca incuba, are held at Yale’s Peabody Museum of Natural History and were collected in central New York state.
“These are beautiful specimens,” said Úna Farrell, invertebrate paleontology collection manager at KU’s Biodiversity Institute. “Preservation of delicate soft parts, like the limbs and eggs in these specimens, only occurs in exceptional circumstances. Usually, only the more robust outer ‘shell’ survives in the rock record. These fossils allow us a glimpse of life on the ocean floor at a time in Earth’s history when N.Y. state was partially under water and south of the equator.”
The research team, headed by Professor David Siveter of the University of Leicester, has termed their find a “nursery in the sea” because the fossilized scene reveals a mother actually carrying her eggs and offspring.
“Some kinds of ostracod lay their eggs into the ocean and hope for the best, but this particular group take care of their young by brooding the embryos under the protection of their shell,” said Farrell. “This specimen has multiple eggs within its shell and even some newly hatched individuals, which are already equipped with a shell of their own.”
The ancient ostracods are relatives of a group alive today that exhibit similar brood-care strategies, indicating that it was effective for millions of years.
“Ostracods are crustaceans, like shrimp, lobster and crabs, and they are very common today — tens of thousands of species of ostracod live in modern oceans, lakes and rivers,” said Farrell. “The modern relatives of Luprisca also take care of their young by brooding, indicating that it was clearly a successful mode of life.”
The team’s findings recently appeared in the peer-reviewed journal Current Biology.
Farrell said the fossil discovery is significant because it pushes back the first instance of brood-based parenting known anywhere on the planet. Farrell’s contribution to the work involved excavating some of the delicate fossils, along with co-author Markus Martin, from rocks of Ordovician age from upstate New York.
“I spent several summers collecting fossils and measuring rock sections at Beecher’s Trilobite Bed site,” she said. “The site has been known for its exceptionally preserved fossils since the late 1800s. The fossils are preserved in pyrite, or ‘fool’s gold,’ which gives them their striking color.”
Farrell also was involved in CT scanning of the fossils at the American Museum of Natural History in New York City.
“The pyrite contrasts nicely with the surrounding shale so that the fossils show up very well in an X-ray,” she said. “A CT scanner takes several X-rays in very thin slices through the fossil, which can then be assembled into a three-dimensional model.”
Farrell said the researchers were able to pin down the age range of the fossils because the ages of rocks in the area are known through isotopic dating and by correlating the fossils with others in the beds. Indeed, part of the difficulty was finding the fossils at the outset. “These fossils are tiny, around one to two millimeters, so spotting them in the first place is a challenge,” said Farrell.
A recent paper co-authored by KU Biodiversity Institute scientists demonstrates the possible effects of climate change on molluscan fauna. While numerous studies have examined potential responses of terrestrial biotas to future climate change, fewer have considered marine realms. The group forecast how marine molluscan faunas might respond to environmental change over the remainder of this century. They tested the hypotheses that suitable areas will shift northwards for studied species, and that species will show varied responses to future climate change. The article, authored by Erin E. Saupe, Jonathan R. Hendricks, A. Townsend Peterson and Bruce S. Lieberman, was published in the Journal of Biogeography here.
The division of Invertebrate Paleontology is exited to welcome Dr. Michelle Casey as a new post-doc. Michelle spent a year teaching at Oberlin College after she completed her PhD at Yale University. She is broadly interested in how ecological interactions change in response to perturbation, and she will be involved in the "Paleoniches" digitization project.
The students and faculty of the Invertebrate Paleontology division would like to congratulate Cori Myers and Curtis Congreve who successfully defended their Ph.D. theses this semester and will graduate May 18th-19th. Cori will be going on to do a post-doctoral fellowship at the prestigious NASA Astrobiology Institute at Harvard and M.I.T., working with Andy Knoll.
Invertebrate collection specimens
For hundreds of years, paleontologists have added fossils to museums around the world, amassing meticulous records of ancient biology, such as the invertebrate paleontology collection at the University of Kansas Natural History Museum and Biodiversity Institute.
There, thousands of drawers hold a record of ancient life that could be especially useful today in predicting how climate change could alter our planet’s biodiversity and distribution of species.
Alas, for years, such collections have come to be known as “dark data” — information that can prove difficult for far-flung researchers and non-academics to access and use.
“When I was in graduate school, if you wanted to track down material at an institution, well, maybe you got lucky and found it,” said Bruce Lieberman, KU professor of ecology and evolutionary biology and senior curator with the division of invertebrate paleontology at the museum. “But to get access to the data, you’d have to contact the collections manager there, and if you wanted to gather data, it would require that a researcher there gather it for you — or you’d have to secure funds to travel yourself sometimes. So when data is hidden like that, it’s like there’s no data at all.”
Now, Lieberman is heading a $600,000 effort funded by the National Science Foundation’s Advancing Digitization of Biological Collections program to digitize thousands of fossils collected over hundreds of years and housed at the KU institute.
Soon, valuable information about fossils’ temporal and geographic distribution in deep time will be available to anyone on the Internet, accessible with a few keystrokes.
Lieberman said that partnerships with other institutions under the NSF grant would allow scientists to complete a fossil record that will more accurately show how climate change could impact species on Earth going forward.
“We know there are certain issues facing the biosphere today and we can sort of measure in ecological time what’s going to happen to the flora and fauna today,” he said. “But if we want a deeper time scale perspective, these fossil data will allow us to look at analogous time periods and analogous climate changes so that we can predict with more accuracy what may happen to life on the planet.”
The digitization process, which will employ undergraduate and graduate students, postdoctoral researchers and a biodiversity informatics developer, will focus on three important time periods — the Ordovician, Pennsylvanian and Neogene — from three major paleobiogeographic regions: the Cincinnati region, American mid-continent and Gulf/Atlantic Coastal Plains.
“I’m focused on invertebrate fossils,” Lieberman said. “Those are species that don’t have a backbone, like snails, clams and their relatives. We have very strong holdings in the Carboniferous period, the time about 290 million years ago. Much of the rock you’d see around this part of Kansas comes from that period. Our deposits are centered on the entire American mid-continent. We have so much information about where those species were found and their distribution through time.”
The endeavor will expand “Specify,” a database program, as well as make the fossil data available online and via portable device digital atlases aimed at amateur paleontologists and K-12 students for use in the field.
Museum collections hold millions of fossils representing information on the distribution of species over space and immense spans of time. They provide large amounts of data useful for studying what causes species to migrate, go extinct, or evolve.
These collections are of great relevance, scientists say, for considering how global change has and will continue to affect life on this planet. However, to reach their scientific potential, the data need to be available online and in a format that facilitates quantitative biogeographic analyses.
A new program from the National Science Foundation, Advancing the Digitization of Biological Collections (ADBC), has awarded a team led by a University of Kansas Biodiversity Institute researcher a $600,000 award to digitize invertebrate fossil collections, including those at KU. The grant will be led by Bruce Lieberman, curator of invertebrate paleontology, as well as Una Farrell, collection manager, and James Beach, director of the informatics program of the Biodiversity Institute.
For this project, scientists will capture information in electronic form about the age and precise location of fossil specimens from several important paleontological collections. They will develop improved computer software to integrate paleontological specimens with modern specimen data and digitize nearly 450,000 specimens in 900 species from museums throughout the United States. The project will focus on three different time periods in the history of life spanning the past 500 million years.
Online digital atlases will be created, illustrating and describing these fossils and providing maps showing where they can be found. In addition, a handheld device "app" will be developed to use these atlases in the field. The online and portable device digital atlases will educate amateur paleontologists and K-12 students about fossils.
This grant for the fossil collections is the first time KU has taken the lead on a Thematic Collections Network project administered through the ADBC program. However, Craig Freeman, curator of botany and senior scientist at the Kansas Biological Survey and Andrew Short, curator of entomology and assistant professor of ecology and evolutionary biology have served as principal investigators (PIs) on two other such projects through the ABDC program and Caroline Chaboo, curator of entomology and assistant professor of ecology and evolutionary biology, has served as a participant. This makes a total of three grants to KU researchers in the first two years of the ADBC program.
For more information about this year’s grant awardees and the National Science Foundation program, visit the NSF news site.
This summer, a new exhibit about the trilobites opened on the third floor of the KU Natural History Museum. The exhibit includes trilobite evolution, morphology (characteristics) and extinction. KU Invertebrate Paleontology staff and faculty, including curator Bruce Lieberman, helped develop the exhibit. Specimens from the invertebrate paleontology collection are on display.
The museum is open Tuesday-Saturday, 9 a.m. to 5 p.m., and Sundays, noon to 5 p.m., and is located at 1345 Jayhawk Blvd.