Tag Archives: plankton

Wie sich Seelilien vor 450 Millionen Jahren ernährten

Computersimulationen ermöglichen Einblick in das komplexe Fressverhalten der Crinoiden, filtrierende Organismen aus der Triaszeit

Mit Computersimulationen haben Wissenschaftlerinnen und Wissenschaftler erstmals rekonstruiert, wie sich „Crinoide“ – wegen ihres pflanzenähnlichen Aussehens auch „Seelilien“ genannt ‒ vor etwa 450 Millionen Jahren ernährten. Die Ergebnisse wurden kürzlich online im Journal PLoS ONE veröffentlicht.
(more…)

Read More

Corals and climate

For corals adjusting to climate change, it’s survival of fattest and most flexible

The future health of the world’s coral reefs and the animals that depend on them relies in part on the ability of one tiny symbiotic sea creature to get fat — and to be flexible about the type of algae with which it cooperates. (more…)

Read More

Establishing World-Class Coral Reef Ecosystem Monitoring in Okinawa

Enduring two typhoons over a three-week period in August, Woods Hole Oceanographic Institution (WHOI) researchers, working in partnership with the Okinawa Institute of Science and Technology Graduate University (OIST), have successfully deployed an OceanCube Observatory System in waters off Motobu Peninsula, Japan — a biodiversity hotspot that is home to ecologically significant coral reefs. The observatory system enables real-time monitoring of temperature, salinity, and other chemical, biological and physical data critical to understanding the health of and changes in the coral reef ecosystem.

Okinawa is situated at the northernmost end of the border between the Pacific and the Indian Oceans. The coral reefs there support the highest diversity of endemic species, plants and animals in the world. These coral reefs are also economically valuable, generating as much as 3 trillion yen ($30 billion) globally, and 250 billion yen ($2.5 billion) in Japan. (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

First Satellite Tag Study for Manta Rays Reveals Habits And Hidden Journeys of Ocean Giants

Using the latest satellite tracking technology, conservationists from the Wildlife Conservation Society, the University of Exeter and the Government of Mexico have completed a ground-breaking study on a mysterious ocean giant: the manta ray.

The research team has produced the first published study on the use of satellite telemetry to track the open-ocean journeys of the world’s largest ray, which can grow up to 25 feet in width.

Researchers say the manta ray—listed as ‘Vulnerable’ by the International Union for the Conservation of Nature (IUCN)—has become increasingly threatened by fishing and accidental capture and now needs more protection. (more…)

Read More

Escalating Arms Race: Predatory Sea Urchins Drive Evolution

ANN ARBOR, Mich.— Nature teems with examples of evolutionary arms races between predators and prey, with the predator species gradually evolving a new mode of attack for each defensive adaptation that arises in the prey species.

These adaptations are often portrayed as reciprocal, with prey and predator acting as two sides in an endless evolutionary tug of war known as co-evolution. (more…)

Read More

Explosive Evolution Need Not Follow Mass Extinctions

In the wake of a mass extinction like the one that occurred 445 million years ago, a common assumption is that surviving species tend to proliferate quickly into new forms, having outlived many of their competitors.

But new research shows that tiny marine organisms called graptoloids did not begin to rapidly develop new physical traits until about 2 million years after competing species became extinct. (more…)

Read More

Rising Carbon Dioxide Levels at End of Last Ice Age Not Tied to Pacific Ocean, As Had Been Suspected

ANN ARBOR, Mich.— After the last ice age peaked about 18,000 years ago, levels of atmospheric carbon dioxide rose about 30 percent. Scientists believe that the additional carbon dioxide—a heat-trapping greenhouse gas—played a key role in warming the planet and melting the continental ice sheets. They have long hypothesized that the source of the gas was the deep ocean.

But a new study by a University of Michigan paleoclimatologist and two colleagues suggests that the deep ocean was not an important source of carbon during glacial times. The finding will force researchers to reassess their ideas about the fundamental mechanisms that regulate atmospheric carbon dioxide over long time scales. (more…)

Read More