Tiny Canadian Satellites Study Brightest Stars * Ancient Peruvian Civilization Fueled by Corn * Skillful Monkeys Crack Nuts * Dolphins Imitate Calls * Permafrost Melting in the Sunlight * How Seals Sleep with Half a Brain
This past week saw the launch of the first two of what will be a constellation of six astronomical "nano-satellites," designed and largely built by Canadian space scientists. The Bright Target Explorer, or BRITE satellites, are 20cm cubes, each with a tiny 3cm telescope. As they orbit the Earth, they will be observing the brightest stars in the sky, which tend also to be the largest and most massive stars as well. Dr. Tony Moffat is Emeritus Professor of Physics at the Université de Montréal and Canadian Principal Investigator on the BRITE constellation
The coastal plain where ancient Peruvians cultivated corn. Credit: Jonathan Haas
Ancient Peruvians, 5,000 years ago, were known to grow corn, but the extent to which they consumed it has been debated for many years. It had been thought that corn was grown only for use in ceremonies. But a new study by Dr. Winifred Creamer, a Professor of Anthropology at Northern Illinois University in DeKalb, has found that corn was not only a significant part of their diet, but they also traded it for other commodities, most notably fish. Microscopic evidence found in fossilized human feces, in soil samples and on stone tools proves that agriculture - especially corn - played a major role in their civilization. These findings also contribute to the theory that these people would not have been able to develop their successful culture - including numerous monumental stone mounds - without a dietary staple like corn.
Capuchin monkeys are some of the few expert tool users in the animal kingdom. The tiny monkeys use large rocks to smash into extremely tough palm-nuts, to get at the tasty kernels inside. Dr. Dorothy Fragaszy, Chair of the Program on Behavioral and Brain Sciences in the Department of Psychology at the University of Georgia, has been studying the Capuchins, and was interested in understanding just how skilled they were at this task. She has found that the monkeys have a well developed technique for positioning the nuts precisely, so their nut-cracking strikes will be most effective.
Dolphin communication has been studied extensively. Their various clicks and squeaks are thought to be a sophisticated type of language. Dolphins are also known to have the capacity to imitate sounds, including other dolphins. But a new study by Dr. Vincent Janik, an Associate Professor of Biology at St. Andrews University in Scotland, has found out which dolphins they imitate and why. Every dolphin has a signature whistle that is known to others in the same social group. When they become separated from each other in the ocean, a dolphin will imitate the sound of its mother's whistle, for example. It's a way of letting the other dolphin know they are near, similar to a human shouting out the name of a person they are trying to locate. Related Links
Melted permafrost creates thermokarst failure, courtesy R. Cory
Climate warming is melting Arctic permafrost at a rate that is alarming many scientists, but it now seems that sunlight is aggravating the problem. Dr. Rose Cory from the Department of Environmental Science and Engineering at the University of North Carolina, and her colleagues, have been looking at a phenomenon called "thermokarst failure," where the land structure can literally fall apart as the permafrost melts. They've found that when this happens, it exposes organic carbon in the permafrost to sunlight. This exposure changes the organic carbon chemically, and accelerates its release into the atmosphere, thus further increasing the rate of global warming.
Marine mammals, including whales, dolphins and some seals, can sleep with half their brain, while the other half remains wakeful, allowing them to swim and watch for predators in the open ocean. Jennifer Lapierre, a PhD student in the Department of Cell & Systems Biology at the University of Toronto, has been studying the neurochemical mechanisms that allow them to do this. By looking at the difference between the sleeping and waking brain, and the half-sleeping brain, she was able to identify which neurotransmitters were involved in sleep, and distinguish them from the ones just associated with inactivity. This may help in understanding the neurochemistry of human sleep disorders as well.
CBC's Rewind takes a look at space travel predictions since 1946. Listen to great clips from the CBC Radio Archives, with new commentary from Bob McDonald, about where space exploration should have taken us by now.