Delayed Echoes

“Everyone has assumed we age by rust,” Kim said. “But then how do you explain animals that don’t age?”

Some tortoises lay eggs at the age of 100, he points out. There are whales that live to be 200, and clams that make it past 400. Those species use the same building blocks for their DNA, proteins and fats as humans, mice and nematode worms. The chemistry of the wear-and-tear process, including damage from oxygen free-radicals, should be the same in all cells, which makes it hard to explain why species have dramatically different life spans.

If aging is not a cost of unavoidable chemistry but is instead driven by changes in regulatory genes, the aging process may not be inevitable. It is at least theoretically possible to slow down or stop developmental drift.

(via Justin Blanton)