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Earliest birds lacked wide diversity of modern descendants, study finds

By Guest PostJune 9, 2014ScienceChina, cretaceous period, diversity, dynamo simulations, evolutionary biology, field museum, geologic evolution, hummingbirds, kometeneis, lander philae, neoproterozoic era, poroeses eis, raumsonde, thomas loerting, tschurjumow gerassimenko, umwelttechnik, university of chicago, weltall

Birds come in astounding variety—from hummingbirds to emus—and behave in myriad ways: they soar the skies, swim the waters and forage the forests. But this wasn’t always the case, according to research by scientists at the University of Chicago and the Field Museum.

The researchers found a striking lack of diversity in the earliest known fossil bird fauna—a set of species that lived at about the same time and in the same habitat. “There were no swans, no swallows, no herons, nothing like that. They were pretty much all between a sparrow and a crow,” said Jonathan Mitchell, a PhD student in the Committee on Evolutionary Biology and lead author of the new study, published May 28 in Proceedings of the Royal Society B. (more…)

MU Researchers Find Rare Fossilized Embryos More Than 500 Million Years Old

By Guest PostMay 4, 2014Nature, Scienceairway diseases, aviation emissions, cambrian explosion, cambrian period, cchi, evolutionary biology, hubei province, marine invertebrates, mark nichols, matt long, pegasus mission, realitaets check, roboter, south china, wolfram burgard

Study methods may help with future interpretation of evolutionary history.

COLUMBIA, Mo. – The Cambrian Period is a time when most phyla of marine invertebrates first appeared in the fossil record. Also dubbed the “Cambrian explosion,” fossilized records from this time provide glimpses into evolutionary biology when the world’s ecosystems rapidly changed and diversified. Most fossils show the organisms’ skeletal structure, which may or may not give researchers accurate pictures of these prehistoric organisms. Now, researchers at the University of Missouri have found rare, fossilized embryos they believe were undiscovered previously. Their methods of study may help with future interpretation of evolutionary history. (more…)

Q&A: What studying networks can tell us about the world and ourselves

By Guest PostFebruary 15, 2014Technologyandrew papachristos, biological epidemics, computers, daniel spielman, david rand, emily erickson, epidemics of violence, evolutionary biology, game theory, genes, june gruber, known as graph, network phenomena, network science, neurons, nicholas christakis, nodes, phenomena, sociologist, sol goldman family, statistical mechanics, studying networks, tradition in mathematics, yale institute, yins

There was an opening ceremony on Feb. 5 for the Yale Institute for Network Science (YINS), dedicated to exploring fundamental properties of networks as they appear throughout the biological, physical, and social sciences.

The interdisciplinary institute will be led by co-directors Nicholas Christakis, the Sol Goldman Family Professor of Social and Natural Science, and Daniel Spielman, the Henry Ford II Professor of Computer Science and Mathematics.

Christakis and Spielman recently met with YaleNews to discuss the nature of networks and the institute’s mission. The following is an edited version of the conversation. (more…)

Scientists reveal why life got big in the Earth’s early oceans

By Guest PostJanuary 24, 2014Nature, Scienceangeomorphs, cambrian explosion, canada, canopy flow models, complex life, david gold, david jacobs, david johnston, early ocean, earth, ecology, evolutionary biology, fossil community, fossil record, foundations, guy narbonne, harvard, large life forms, life, marc laflamme, matthew clapham, MIT, modeling technique, multicellular eukaryotes, multicellular organism, newfoundland, nutrient carrying, nutrient uptake, nutrients from seawater, ocean flow, queens university, roger summons, uc santa cruz, ucla biologist, university of toronto, variety of scale

Why did life forms first begin to get larger and what advantage did this increase in size provide? UCLA biologists working with an international team of scientists examined the earliest communities of large multicellular organisms in the fossil record to help answer this question. (more…)

With Fewer Hard Frosts, Tropical Mangroves Push North

By Guest PostJanuary 4, 2014Environmentatlantic coast, australia, biodiversity, birds, brazil, climate change, coastal insects, daniel s gruner, evolutionary biology, florida, florida atlantic coast, landsat 5, mangrove forests, Mexico, miami, NASA, new zealand, palm beach county, peru, rising sea levels, salt marshes, temperature, tropical mangroves, university of maryland

COLLEGE PARK, Md. – Cold-sensitive mangrove forests have expanded dramatically along Florida’s Atlantic Coast as the frequency of killing frosts has declined, according to a new study based on 28 years of satellite data from the University of Maryland and the Smithsonian Environmental Research Center in Edgewater, Md.

Between 1984 and 2011, the Florida Atlantic coast from the Miami area northward gained more than 3,000 acres (1,240 hectares) of mangroves. All the increase occurred north of Palm Beach County. Between Cape Canaveral National Seashore and Saint Augustine, mangroves doubled in area. Meanwhile between the study’s first five years and its last five years, nearby Daytona Beach recorded 1.4 fewer days per year when temperatures fell below 28.4 degrees Fahrenheit (-4 degrees Celsius). The number of killing frosts in southern Florida was unchanged. (more…)

Dogs likely originated in Europe more than 18,000 years ago, UCLA biologists report

By Guest PostNovember 16, 2013Nature, Scienceancient dog fossil, ancient hunter, carnivore, co evolutionary process, coyotes, daniel greenfield, dog, dog like animals, dogs from europe, domestic dogs, druid peak, east asia, Europe, european hunter, european wolves, evolutionary biology, finland, fossil, genetic analysis, genetic data, illinois, klaus koepfli, koster archaeological site, late pleistocene, middle east, middle east origin, migration, mitochondrial dna, modern dogs, North America, olaf thalmann, old world, origin, proximity to humans, robert wayne, species, two wolves, ucla biologist, university of turku, western russia, wolf like animals, yellowstone national park

Wolves likely were domesticated by European hunter–gatherers more than 18,000 years ago and gradually evolved into dogs that became household pets, UCLA life scientists report.

“We found that instead of recent wolves being closest to domestic dogs, ancient European wolves were directly related to them,” said Robert Wayne, a professor of ecology and evolutionary biology in UCLA’s College of Letters and Science and senior author of the research. “This brings the genetic record into agreement with the archaeological record. Europe is where the oldest dogs are found.” (more…)

The secret math of plants: UCLA biologists uncover rules that govern leaf design

By Guest PostNovember 5, 2013Natureallometric analysis, carbohydrate based, cell wall, christine scoffoni, cross section, embedded pieces, evolutionary biology, grace john, isometric, lawren sack, leaf design, leaf surface area, leaf thickness, mesophyll, plants, secret math, ucla biologist

Life scientists from UCLA’s College of Letters and Science have discovered fundamental rules of leaf design that underlie plants’ ability to produce leaves that vary enormously in size. In their mathematical design, leaves are the “perfect machines,” said Lawren Sack, a professor of ecology and evolutionary biology and senior author of the research.

The UCLA team discovered the mathematical relationships using “allometric analysis,” which looks at how the proportions of parts of an organism change with differences in total size. This approach has been used by scientists since Galileo but had never before been applied to the interior of leaves. (more…)

Brown and High Schools: Teaching Teens About Climate Change, Health

By Guest PostDecember 14, 2012Educationallergies, anatomy course, breakthrough providence, brown university, climate change, curriculum, david upegui, ecology, evolutionary biology, global food supply, global warming, high school teachers, human health, infectious disease, jessica fields, katherine smith, mark schlissel, mold, name tags, natural habitat, pollen, tram bui, vicki santos silva

A Brown University class on the effect that climate change could have on human health has produced a free new curriculum for high school teachers. The nine-module unit, which reflects feedback from teachers, includes lecture background and ideas for warm-ups, in-class activities, and assessment.

PROVIDENCE, R.I. [Brown University] — Katherine Smith’s students had to wait until they came to Brown University to learn how climate change could affect human health. Now that Smith and her fall semester class have developed a rich new curriculum on the subject for high school teachers, future 10th to 12th graders might not have to wait so long.

The curriculum, a nine-module set of backgrounders, lecture notes and suggested lesson plans and classroom activities, is now available for free download. In 180 total pages, it covers topics ranging from an overview of climate change to more specific units such as how global warming could affect infectious disease, allergies, and the global food supply. (more…)

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