Tag Archives: ecologist

Predators and isolation shape the evolution of ‘island tameness,’ providing conservation insights

ANN ARBOR — Charles Darwin noted more than 150 years ago that animals on the Galapagos Islands, including finches and marine iguanas, were more docile than mainland creatures. He attributed this tameness to the fact that there are fewer predators on remote islands. (more…)

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Live longer? Save the planet? Better diet could nail both

New study shows healthier food choices could dramatically decrease environmental costs of agriculture

As cities and incomes increase around the world, so does consumption of refined sugars, refined fats, oils and resource- and land-intense agricultural products such as beef. A new study led by University of Minnesota ecologist David Tilman shows how a shift away from this trajectory and toward healthier traditional Mediterranean, pescatarian or vegetarian diets could not only boost human lifespan and quality of life, but also slash greenhouse gas emissions and save habitat for endangered species. (more…)

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Tiniest Catch: UA Scientists’ Fishing Expedition Reveals Viral Diversity in the Sea

Using bacteria as bait, UA scientists caught wild ocean viruses and found that the genetic lines between virus types in nature are less blurred than previously thought.

A fishing expedition of microscopic proportions led by University of Arizona ecologists revealed that the lines between virus types in nature are less blurred than previously thought. (more…)

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Warmer temperatures push malaria to higher elevations

ANN ARBOR — Researchers have debated for more than two decades the likely impacts, if any, of global warming on the worldwide incidence of malaria, a mosquito-borne disease that infects more than 300 million people each year.

Now, University of Michigan ecologists and their colleagues are reporting the first hard evidence that malaria does—as had long been predicted—creep to higher elevations during warmer years and back down to lower altitudes when temperatures cool. (more…)

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Mutual benefits: Stressed-out trees boost sugary rewards to ant defenders

ANN ARBOR — When water is scarce, Ecuador laurel trees ramp up their investment in a syrupy treat that sends resident ant defenders into overdrive, protecting the trees from defoliation by leaf-munching pests.

The water-stressed tropical forest trees support the production of more honeydew, a sugary excretion imbibed by the Azteca ants that nest in the laurels’ stem cavities. In return, ant colonies boost their numbers and more vigorously defend the life-sustaining foliage. (more…)

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The Failing Freezer: How Soil Microbes Affect Global Climate

With a $3.9 million grant from the U.S. Department of Energy, a UA-led international collaboration studies how microbes release greenhouse gases as they gain access to nutrients in the soil thawing under the influence of warmer global temperatures.

The U.S. Department of Energy has awarded $3.9 million to an international collaboration led by University of Arizona ecologists Scott Saleska and Virginia Rich to study how microbes release greenhouse gases as they access nutrients in thawing permafrost soils under the influence of a warmer climate.  (more…)

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UA Study: Evolution Too Slow to Keep Up With Climate Change

A study led by a UA ecologist has found that many species evolve too slowly to adapt to the rapid climate change expected in the next 100 years.

Many vertebrate species would have to evolve about 10,000 times faster than they have in the past to adapt to the rapid climate change expected in the next 100 years, a study led by a University of Arizona ecologist has found.

Scientists analyzed how quickly species adapted to different climates in the past, using data from 540 living species from all major groups of terrestrial vertebrates, including amphibians, reptiles, birds and mammals. They then compared their rates of evolution to rates of climate change projected for the end of this century. This is the first study to compare past rates of adaption to future rates of climate change.  (more…)

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Deep Biosphere Harbors Active, Growing Communities of Microorganisms

The deep biosphere—the realm of sediments far below the seafloor—harbors a vast ecosystem of bacteria, archaea, and fungi that are actively metabolizing, proliferating, and moving, according a new study by scientists at Woods Hole Oceanographic Institution (WHOI) and the University of Delaware (UD).

“This is the first molecular evidence for active cell division in the deep biosphere,” says WHOI postdoctoral investigator Bill Orsi, who was the lead author on the study. Previous studies and models had suggested cells were alive, but whether the cells were actually dividing or not had remained elusive. (more…)

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