The future is ... plastics, and that's not a good thing. Our favorite disposable material is contaminating the oceans in ways we'd never anticipated, and you'll hear today about just how long we'll be living with Oceans of Plastic. Plus, we'll hear how music lessons for very young children can influence their brain development; we'll discover a small mammal that can smell in stereo; we'll find out how a new invasive ant is pushing out another invasive ant; and we'll hear about a new approach to artificial tissues that combines biology and technology.
It would be difficult to get through a day without plastic. Your toothbrush, your fridge, your computer, your car, your cell phone, your water bottle - all made with plastic. But the very thing that makes plastic so versatile and valuable also makes it one of the most persistent and widespread environmental problems on the planet. Plastic waste is everywhere, littering our parks and beaches and mountain trails, filling our garbage dumps - and perhaps most alarmingly - polluting our oceans. Plastic litter has been found in every single part of the seven seas - from the floor of the Arctic Ocean to the farthest reaches of the Pacific. And it's not going away. Every single piece of plastic that entered our oceans over the past 60 years is still there. Award-winning Canadian science writer Alanna Mitchell has written an e-book about this ecological crisis, called, Invisible Plastic: What happens when your garbage ends up in the ocean. In it, she details how millions of microscopic pieces of plastic now blanket our seven seas, disturbing the delicate ecological balance, and inserting uncertainties into a formerly predictable system.
If you started taking music lessons before the age of seven, you would benefit from permanent changes in the area of the brain linked to motor skills. That is the finding of a new study by Dr. Virginia Penhune, a Psychology Professor at Concordia University in Montreal. In her study, adult musicians were divided into two groups, those who began lessons before age seven, and those who started music instruction after age seven. Brains scans determined that those who started earlier had more and thicker fibres in a tissue known as white matter in a part of the brain called the corpus callosum. The corpus callosum plays an important role in a person's ability to coordinate both hands - a significant skill for a musician. When the brain scans of those musicians who started playing after age seven were compared to a third group comprised of non-musicians, there was little difference. This suggests that there is a critical period at a young age where musical training interacts with brain development to produce these positive results.
Because of our paired sensory organs, we're used to the idea of stereo hearing, which helps us locate sound, and stereo vision, which provides depth perception. Stereo smell, however, is a stranger idea. But scientists have surmised that paired nostrils could, theoretically, provide slightly different odor signals that might help animals find food. Dr Ken Catania, the Stevenson Professor of Biological Sciences at Vanderbilt University in Nashville, Tennessee, has found that the common mole, the nearly blind, subterranean hunter, actually does smell in stereo to find its prey. In experiments with moles, Dr. Catania temporarily blocked single nostrils and switched the inputs to the mole's nose using tubes, and found this confused the animal's normally excellent odor location abilities, suggesting they do smell in stereo.
Asian Needle ant devouring a termite, its favourite food. Courtesy Benoit Guenard
Argentine ants arrived in North America in the 1920's in the ballast of ships. Since that time, this very aggressive invader has spread throughout the southern United States and to most continents of the world, in what is referred to as 'supercolonies'. These include millions of workers and thousands of queens in nests that can span many kilometres and easily replace native species. But a new study by Dr. Eleanor Spicer Rice, an entomologist from North Carolina State University in Raleigh, has found that another invasive ant has been able to move in on the Argentine ant's territory. The Asian Needle ant, common to China and Korea, is larger and equipped with a venomous stinger. How it arrived is unclear, but it has been able to move into Argentine ant supercolonies without any resistance. The researchers believe that because the Asian Needle ant emerges from its winter dormant state much sooner than the Argentine ant, it has earlier access to resources and also begins growing its population much earlier. Related Links
To replace or repair damaged or diseased organs, scientists are working on two approaches. Some are exploring building artificial organs, while others are attempting to grow new organs from cells in the lab. Neither approach has been completely successful. But Dr. Ali Khademhosseini, a Canadian scientist and associate professor at the Harvard/MIT Division of Health Science and Technology, and at Harvard Medical School, is exploring a hybrid approach. In a new experiment, he combined heart cells and carbon nanotubes to create a kind of hybrid tissue. The nanotubes both reinforce the cells, making the tissue stronger, and conduct electricity so that the electrical signal that causes normal heart tissue to beat or contract moves through the tissue efficiently. The technology might eventually be used for patches to repair heart tissue, or for robotic devices driven by organic muscle.