Tag Archives: evolutionary change

Cotsen researcher finds evidence of ‘unnatural selection’ in popular Panamanian seafood

Caribbean fighting conch used to be harvested with more meat, but evolved to mature at smaller size

Like most residents of Panama’s Isla Colón, UCLA archaeologist Thomas Wake has enjoyed more than a few plates of Caribbean fighting conch in the 11 years he’s operated his field lab on the island’s north shore.

“They’re stigmatized as a poor people’s food, but they’re good,” said Wake, a lab director at the Cotsen Institute of Archaeology in UCLA’s College of Letters and Science. “They taste a lot like abalone or calamari.” (more…)

Read More

Analysis of Dinosaur Bone Cells Confirms Ancient Protein Preservation

A team of researchers from North Carolina State University and the Palo Alto Research Center (PARC) has found more evidence for the preservation of ancient dinosaur proteins, including reactivity to antibodies that target specific proteins normally found in bone cells of vertebrates. These results further rule out sample contamination, and help solidify the case for preservation of cells – and possibly DNA – in ancient remains.

Dr. Mary Schweitzer, professor of marine, earth and atmospheric sciences with a joint appointment at the North Carolina Museum of Natural Sciences, first discovered what appeared to be preserved soft tissue in a 67-million-year-old Tyrannosaurus Rex in 2005. Subsequent research revealed similar preservation in an even older (about 80-million-year-old)Brachylophosaurus canadensis. In 2007 and again in 2009, Schweitzer and colleagues used chemical and molecular analyses to confirm that the fibrous material collected from the specimens was collagen. (more…)

Read More

Not a One-Way Street: Evolution Shapes Environment of Connecticut Lakes

Environmental change is the selective force that preserves adaptive traits in organisms and is a primary driver of evolution. However, it is less well known that evolutionary change in organisms also trigger fundamental changes in the environment.

Yale University researchers found a prime example of this evolutionary feedback loop in a few lakes in Connecticut, where dams built 300 years ago in Colonial times trapped a fish called the alewife.

In a study published May 23 in the journal Proceedings of the Royal Academy B, the Yale team describes how this event fundamentally changed the structure of the alewife and, with it, the water flea that the alewife feeds upon and the food chain that supports them both. (more…)

Read More

Coyotes “Shrank,” Wolves Did Not, After Last Ice Age and Megafaunal Extinctions

*Once large and wolf-like, coyotes ultimately became much smaller*

When the last ice age ended more than 10,000 years ago, many large species of mammals went extinct and others underwent changes in appearance.

But what caused evolutionary changes to take place in the mammals that remained alive?

A study by Julie Meachen of the National Science Foundation (NSF) National Evolutionary Synthesis Center and Josh Samuels of the John Day Fossil Beds National Monument reveals that gray wolves and coyotes, once more similar in size, took the extinction in different strides. (more…)

Read More

Evolution is Written All Over Your Face

Why are the faces of primates so dramatically different from one another?

UCLA biologists working as “evolutionary detectives” studied the faces of 129 adult male primates from Central and South America, and they offer some answers in research published today, Jan. 11, in the early online edition of the journal Proceedings of the Royal Society B. The faces they studied evolved over at least 24 million years, they report.

“If you look at New World primates, you’re immediately struck by the rich diversity of faces,” said Michael Alfaro, a UCLA associate professor of ecology and evolutionary biology and the senior author of the study. “You see bright red faces, moustaches, hair tufts and much more. There are unanswered questions about how faces evolve and what factors explain the evolution of facial features. We’re very visually oriented, and we get a lot of information from the face.” (more…)

Read More

Pollution Triggers Genetic Resistance Mechanism in a Coastal Fish

For 30 years, two General Electric facilities released about 1.3 million pounds of polychlorinated biphenyls (PCBs) into New York’s Hudson River, devastating and contaminating fish populations. Some 50 years later, one type of fish—the Atlantic tomcod—has not only survived but appears to be thriving in the hostile Hudson environment.

Researchers from Woods Hole Oceanographic Institution (WHOI) have joined colleagues from New York University (NYU) and NOAA to investigate this phenomenon and report that the tomcod living in the Hudson River have undergone a rapid evolutionary change in developing a genetic resistance to PCBs. (more…)

Read More