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The Winners of Mass Extinction: With Predators Gone, Prey Thrives

By Guest PostMay 11, 2011Scienceage of fishes, age of the crinoids, crinoid fossils, devonian era, devonian period, ecology, ecosystem, Environment, fish, fossil record, fossils, hangenberg event, lauren sallan, lotka volterra cycles, marine vertebrate, mass extinction, modern biodiversity, natural experiment, ocean life, ohio state university, paleontologist, population of prey species, predator prey dynamics, predator prey relationships, residual defenses, robert nicholls, thomas kammer, university of chicago, william ausich

*Extinction of fishes 360 million years ago created natural ecology experiment*

In present-day ecology, the removal or addition of a predator in an ecosystem can produce dramatic changes in the population of prey species. For the first time, scientists have observed the same dynamics in the fossil record, thanks to a mass extinction that decimated ocean life 360 million years ago.

What was bad for fish was good for the fish’s food, according to a paper published online in Proceedings of the National Academy of Sciences. Researchers from the University of Chicago, West Virginia University and The Ohio State University found that the mass extinction known as the Hangenberg event produced a “natural experiment” in the fossil record, with results that mirror modern observations about predator-prey relationships. (more…)

Uncertain Future for Joshua Trees Projected with Climate Change

By Guest PostMarch 27, 2011Environment, Naturecalifornia, climate change, climate warming, climatic tolerances, ecologis, ecology, fossil record, jon eischeid, joshua trees, ken cole, kenneth cole, kirsten ironside, models of future climate, mojave desert, nevada, north american yucca, packrats, shasta ground sloth, southwest, squirrels, state of the art climate models, temperature

FLAGSTAFF, Ariz. — Temperature increases resulting from climate change in the Southwest will likely eliminate Joshua trees from 90 percent of their current range in 60 to 90 years, according to a new study led by U.S. Geological Survey ecologist Ken Cole.

The research team used models of future climate, an analysis of the climatic tolerances of the species in its current range, and the fossil record to project the future distribution of Joshua trees. The study concludes that the species could be restricted to the northernmost portion of its current range as early as the end of this century. Additionally, the ability of Joshua trees to migrate via seed dispersal to more suitable climates may be severely limited. (more…)

Invisible Invasive Species Altering Ecosystems

By Guest PostDecember 10, 2010Environmentair temperatures, asian carp, australia, blue green algae, brackish diatom, climate change, cyanobacteria, dramatic fashion, ecology, ecosystems, elena litchman, european lakes, global change, great lakes, gypsy moths, invasive microbes, invasive species, lake michigan, macroorganism, malaria, microbial invaders, nitrogen fixing rhizobium, nonpathogenic microbes, north american, pathogenic parasitic fungus, portugal, scientific research, subtropical, temperate latitudes, tropical, zebra mussels

Elena Litchman, associate professor of ecology, who works at MSU's Kellogg Biological Station. Image credit: Michigan State University

EAST LANSING, Mich. — While Asian carp, gypsy moths and zebra mussels hog invasive-species headlines, many invisible invaders are altering ecosystems and flourishing outside of the limelight.

A study by Elena Litchman, Michigan State University associate professor of ecology, sheds light on why invasive microbial invaders shouldn’t be overlooked or underestimated.

“Invasive microbes have many of the same traits as their larger, ‘macro’ counterparts and have the potential to significantly impact terrestrial and aquatic ecosystems,” said Litchman, whose research appears in the December issue of Ecology Letters. “Global change can exacerbate microbial invasions, so they will likely increase in the future.” (more…)

The Giant Panda: The Good News

By PravdaDecember 5, 2010Environment, Natureartificial insemination, bamboo pole, chengdu breeding center, chengdu panda breeding research center, China, cubs, ecology, endangered species, Environment, extinction, giant panda, pr china, reproductive cycle, scientists, timothy bancroft-hinchey, twin swapping technique, viagra

Close up of a cute baby 7-month old panda cub in the Wolong Nature Reserve in Sichuan, China. Image credit: Sheila Lau. Source: Wikipedia

Finally some good news on the environment, on ecology and on the Giant Panda: a revolutionary new technique developed by the PR China’s Chengdu breeding center seems certain to assure that greater numbers of this endangered species can be raised in thereby save it from extinction.

Just 1,600 Giant Pandas live in the wild, in 40 government-controlled panda reserves in the People’s Republic of China. The new breeding program has raised the number of animals bred in captivity to 300, while just this year 19 cubs have been born after artificial insemination programs in China’s two main breeding centers.

Breeding Giant Pandas in captivity is no easy task. They have the strangest gestation period which can range from eleven weeks to eleven months, they appear not to be sexually aroused by being held in captivity, females are on heat for 72 hours a year and are fertile during a 12 to 24-hour window inside that period. The small size of the male penis also means the mating position has to be exactly right, and this is not always possible in captivity. (more…)

Biologists Report More Bad News for Polar Bears

By Guest PostNovember 24, 2010Environment3-d computer models, brown bears, climate change, ecology, Environment, extreme environment, genetic studies, global warming, graham slater, grizzly bears, ice ages, polar bears, van valkenburgh, vegetables

*Climate change will force them south, where they are unsuited for the diet*

A polar bear breaks through thin Arctic Ocean ice Aug. 23, 2009. Image credit: Canadian Coast Guard/USGS

Will polar bears survive in a warmer world? UCLA life scientists present new evidence that their numbers are likely to dwindle.

As polar bears lose habitat due to global warming, these biologists say, they will be forced southward in search of alternative sources of food, where they will increasingly come into competition with grizzly bears.

To test how this competition might unfold, the UCLA biologists constructed three-dimensional computer models of the skulls of polar bears and grizzly bears — a subspecies of brown bears — and simulated the process of biting. The models enabled them to compare the two species in terms of how hard they can bite and how strong their skulls are. (more…)

Catastrophic Drought Looms for Capital City of Bolivia

By Guest PostNovember 13, 2010Environmentandean ecosystems, andean forests, andes, Bolivia, carbonate deposition, catastrophic drought, climatologist, ecology, fit, florida institute of technology, interglacial periods, lake poopo, lake titicaca, mark bush, paul filmer, peru, sherilyn fritz, temperatures rise, vegetation change

*Historical ecology of the Andes indicates desert-like setting on the horizon*

Catastrophic drought is on the near-term horizon for the capital city of Bolivia, according to new research into the historical ecology of the Andes.

If temperatures rise more than 1.5 to 2 degrees Celsius (3 to 5 degrees Fahrenheit) above those of modern times, parts of Peru and Bolivia will become a desert-like setting.

About the image: Lake Titicaca from space. Its outline may look very different in the future. Image credit: NASA (more…)

Are Wolves Saving Yellowstone’s Aspen Trees from Elk?

By Guest PostSeptember 3, 2010Naturearthur middleton, aspen, aspen tree, carnivores, cheetahs, ecology, elk, erik jules, hunting strategies, jedediah brodie, landscape of fear, matthew kauffman, predators, u s geological survey, wolves, yellowstone national park

LARAMIE, Wy. — Previous research has claimed that the reintroduction of wolves to Yellowstone National Park in 1995 is helping restore quaking aspen in risky areas where wolves prowl. But apparently elk hungry for winter food had a different idea.

(more…)

Shade-coffee farms support native bees that help maintain genetic diversity in remnant tropical forests

By Guest PostJuly 27, 20101 commentEnvironment, Natureafricanized honeybees, Berkeley, biodiverse tropical regions, biodiversity, biologist, buzz, canopy of trees, chiapas, christopher dick, ecology, evolutionary biology, m. affinis, Mexico, miconia affinis, migratory birds, native bees, native trees, pollination, role, saquiyac tree, shade-coffee farms, shade-grown coffee, shalene jha, tropical forest, university of california, university of michigan

ANN ARBOR, Mich. — Shade-grown coffee farms support native bees that help maintain the health of some of the world’s most biodiverse tropical regions, according to a study by a University of Michigan biologist and a colleague at the University of California, Berkeley.

(more…)

Tag Archives: ecology