Biodiversity in Antarctica under threat
Previous studies have suggested that Antarctica and the Southern Ocean are in much better environmental shape than the rest of the world, but a study recently published in PLOS Biology suggests that biodiversity and conservation are still concerning issues for this region. The researchers evaluated the future outlook of biodiversity in Antarctica, according to the Convention on Biological Diversity’s Aichi targets. They found that Antarctica faces similar challenges to biodiversity as the rest of the world — a surprising result, since conservation management in the remote region is thought to be top-notch. “Despite our findings, there are great opportunities for positive action,” says co-author and Monash University professor Melodie McGeoch. “The agreements under the Antarctic Treaty System lend themselves to effective action, and nations have recently reinforced their desire to protect the region’s biodiversity.”
Birds’ blind spots vary in length depending on species
Like many animals, birds have binocular vision, which allows them to perceive depth by overlapping two fields of view. Since a bird’s eyes are located on either side of its head, it also has a blind spot in front of its head. While it’s easy to dismiss what birds can’t see, a new study shows that the length of the blind spot actually plays an important role in bird vision. The researchers’ examination of published data on the visual fields of 40 species of birds, as well as measurements of the beaks and skulls of museum specimens, revealed that longer-beaked birds had narrower fields of binocular vision, but they also had shorter blind gaps in front of their heads. This finding shows that the size of the beak and the length of the blind spot both play a big role in birds’ sight.
Environmental changes affect slime mold decision-making
A ‘noisy’ decision-making process may enhance the foraging capabilities of the slime mold Physarum polycephalum. To investigate how the slime mold would react to changing environments, the authors of this new study used a maze model to mathematically examine the effects of intermittent light exposure — typically perceived as a risk — on the path taken by the slime mold to travel from one food source to the other. The ‘virtual’ slime mold appeared to be more adept at optimizing this path when it used a ‘noisy’ decision-making process that maximized long-term benefit, instead of attempting to make a separate decision for each flash of light. “Our work investigates decision making in the true slime mold, Physarum polycephalum, one of the most widely used model organisms to study self-organization in biological systems,” says co-author Bernd Meyer. “It reveals that noise in self-organized decision making is a fundamental driver for the ability to flexibly adapt behavior in changing environments.” Further research could explore whether these predictions extend to other self-organized biological systems, such as ant colonies, honeybee hives, and even human communities.
Image Credit: Steven L. Chown