How blue can eggs get?

Do differences in egg colour mean anything? Some scientists suspect that they do. Not between white and brown, but the difference in the intensity of the blue-green of eggs of many species in which mates share parental duties.

Do differences in egg colour mean anything? Some scientists suspect that they do. Not between white and brown, but the difference in the intensity of the blue-green of eggs of many species in which mates share parental duties. The colour is because of the pigment biliverdin, which has antioxidant qualities. Some scientists suggest that a more intense colour may be a signal to spur the male to care for the offspring. The idea is that if the female has antioxidants to spare, she must have well-developed immune defences. Thus her eggs must be in good shape, too, and worth caring for. Judith Morales of the National Museum of Natural Sciences in Madrid and colleagues discovered that more intense the blue-green colour as measured by a spectrophotometer, the more maternal antibodies the yolk contained. These antibodies provide passive immunity to the fledgling and are critical to its survival. Colour intensity was also strongly associated with a likelihood the fledgling would survive the first several weeks.

NYT

Legendary shell life

Pause to note the death of Adwaitya, an Aldabran tortoise who died last Wednesday at the Kolkata zoo. He is believed to have been about 250, nearly 80 years older than the next-oldest animal, a 176-year-old Galapagos tortoise living in Australia. We may marvel at the fact of living to such a great age. But tortoise watchers of an earlier era were more likely to wonder why tortoises lived to such a great age. Such a very old tortoise as Adwaitya, which means 8220;the one and only,8221; must have wondered, in turn, why Providence bestows such short lives upon humans. He had lived in the Kolkata zoo since 1875 and was one of four tortoises captured from Aldabra8212;which one tortoise historian calls a 8220;low coralline atoll 8230; in a little-visited part of the Indian Ocean about 400 km north of Madagascar8221;8212;and presented to Lord Robert Clive, who was the architect, if that is the word, of the British empire in India. If Adwaitya was truly 250, he was born in the same year as Amadeus Mozart.