Your Eyes Do Layered Image Processing
May 12, 2005
Computer users familiar with Photoshop and other image processing programs know that an image can be divided into “layers” for making color corrections, evening out contrast and enhancing details. Your eyes do that, too, says Alan Gilchrist in Current Biology.1 He shows a stunning optical illusion to make the point: transparent chess pieces against differing […]
Do Neurologists Understand Brain Evolution?
April 3, 2005
Jane Bradbury wrote a feature piece for PLOS Biology recently,1 entitled, “Molecular Insights into Human Brain Evolution.” Help us find the insights. First, she marvels on how “humans sit on top of the pile when it comes to relative brain size.” Then she marvels at how quickly the human brain apparently evolved compared to apes. […]
If I Only Had a Brain…
March 8, 2005
The scarecrow didn’t know what he was asking for. Look what Steven E. Hyman of Harvard says about the human brain and nervous system in the 8 March 2005 issue of Current Biology:1 The nervous system processes sensory information and controls behavior by performing an enormous number of computations. These computations occur both within cells […]
Are Humans Still Evolving?
January 18, 2005
Science Now asks the question, “are humans still evolving?” Comparisons of genes and chromosomes between different people groups from Asia, Europe and Africa are challenging the view that there is one human genome. Some long stretches of DNA are inverted in some groups, and women so affected seem to have more children on average, even […]
Robots Dont See as Well as You Do
January 12, 2005
Robot designers are still working on ways to emulate the human eye. Just when you thought digital cameras were all the rage, we learn from EurekAlert they are miserable substitutes when put into the eye sockets of robots. Robot-vision export Vladimir Brajovic explains: Often, when we take a picture with a digital or film camera, […]
Why You Breathe Deep to Sniff a Flower
January 6, 2005
It may sound like a 747 when your uncle blows his nose, but scientists at Imperial College found nose airflow to be more complicated than the aerodynamics of a jumbo jet’s wing, according to a press release by the reporting the Biotechnology and Biological Sciences Research Council . They made a 3D model of the […]
Monkeys Have No Ear for Music
December 13, 2004
Consonance and dissonance have no meaning to monkeys, studies have shown. Nature Science Update reported on experiments on cotton-top tamarins showing that, unlike humans, they do not find consonant tones more pleasing than dissonant ones. “If you want to look at the evolution of music it’s important to do these types of studies,” says Laurel […]
Haeckel Vindicated? Parathyroid Glands from Gills?
December 7, 2004
“Human gland evolved from gills” trumpeted a BBC News science article without apology.* It gives uncontested press to a team from King’s College that is claiming the human parathyroid glands evolved from gills. This is claimed on the basis that they have similar functions (calcium regulation) and are located in the neck region. Fish have […]
Did Language Evolve by Natural Selection?
October 27, 2004
In the Oct 14 issue of Nature,1 Gary Marcus (Dept. of Psychology, New York University) appears conflicted about how human language arose. He wants to attribute it to a Darwinian process: If, as François Jacob famously argued, evolution is like a tinkerer who builds something new by using whatever is close at hand, then from […]
Disembodied Brain Flies Jet Aircraft
October 25, 2004
Researchers at University of Florida claim to have connected rat brains neurons in a dish to electrodes, which learned to run an F22 flight simulator. We can’t speak to the validity of this claim or its interpretation, but what stands out in the article is the awe over the computational abilities of the human brain: […]
Your Brain Hums While Idling
October 11, 2004
Your brain is 100% occupied when watching and concentrating on things, and still processing at 80% in the dark when idle, say researchers at University of Rochester. Opening your eyes only adds 20% more brain activity to the 80% while in neutral. The amount of neural processing going on in idle mode surprised the researchers. […]
Burnt Bridges, Brownian Ratchets, and Self-Propelled Motors Keep Skin Young Looking
October 1, 2004
Rock climbers and cavers are familiar with mechanical devices called ascenders that enable them to climb ropes safely and easily. Ascenders slide up the rope in one direction, but latch onto it tightly when pulled the other direction. Now imagine the ascender by itself, hanging on the rope, in a flurry of winds blowing in […]
Your Eyes Have Automatic Light Meters
October 1, 2004
Every pupil knows that pupils constrict in bright light and dilate in dim light, but how? Physiologists had assumed the retina signalled the iris muscles, but now it appears there is an independent mechanism in the iris itself, at least in birds, and probably in mammals, too. A report in EurekAlert summarizes a finding from […]
Natural Selection Demonstrated in European Heart-Disease Gene?
September 7, 2004
Stephen Wooding (U. of Utah) is elated. He sees an “exciting trend” in genetic research that might, finally, demonstrate positive natural selection acting on a gene with a clear phenotypic effect (measurable outward benefit). Writing in the Sept. 7 Current Biology,1 he mentions a few recent papers suggesting this connection, but focuses particularly on one […]
What Would a Man Born Blind See With New Eyes?
August 26, 2004
The Bible records an instance of a man born blind miraculously healed, who was immediately able to walk and recognize things. Scientists had doubted whether a blind person suddenly able to see would understand the world of vision at all, or be able to make any sense of his new sense. Then a real world […]