How Peacocks Got Their Colorful Tails
Some researchers are now turning their attention from why showy traits evolved, to how they evolved and why they tend to do so more often in males. To help answer these questions, scientists at the University of Wisconsin-Madison studied fruit fly derrieres and found that ancient genetic switches have evolved to manipulate the appearance of animals in a way that favored their selection as mates, providing a possible explanation for how peacocks evolved their spectacular tails.
Kamikaze bacteria illustrate evolution of co-operation
Suicidal Salmonella sacrifice themselves to allow their clones to get a foothold in the gut.
Bacteria can commit suicide to help their brethren establish more damaging infections — and scientists think that they can explain how this behaviour evolved.
The phenomenon, called self-destructive cooperation, can help bacteria such asSalmonella typhimuriumand Clostridium difficile to establish a stronghold in the gut.
By studying mice infected with S. typhimurium, researchers from Switzerland and Canada have now demonstrated how this 'kamikaze' behaviour arose.