News by Subject Agriculture

Evolutionary arms races between marine animals overhauled ocean ecosystems on scales similar to the mass extinctions triggered by global disasters, a new study shows.

A coordinated conservation effort that removed rats from Hawadax Island, formerly known as "Rat Island," has become a new example of how ecosystems can fully recover to their natural state in little more than a decade. The results are described in a report led by a UC San Diego scientist.

Sea otters maintain the balance of kelp forest ecosystems by controlling populations of sea urchins, which are voracious kelp grazers. Since 2014, however, California's kelp forests have declined dramatically, and vast areas of the coast where kelp once thrived are now "urchin barrens," the seafloor carpeted with purple sea urchins and little else. This has occurred even in Monterey Bay, which hosts a large population of sea otters. A new study explains what happened.

Scientists reporting in the journal Current Biology on March 8 have discovered two species of sacoglossan sea slug that can do even better, shedding and then regenerating a whole new body complete with the heart and other internal organs. The researchers also suggest that the slugs may use the photosynthetic ability of chloroplasts they incorporate from the algae in their diet to survive long enough for regeneration.

Findings reveal that demographics such as race and population density, as well as health indices such as cancer rates and food insecurity, show strong correlations with water quality across Virginia.

Shark scientists at Georgia Aquarium, Scripps Institution of Oceanography at UC San Diego, and Dalhousie University are challenging the status quo in shark and ray mating research in a new study that looks at biological drivers of multiple paternity in these animals.