Washington (AFP) – Scientists have discovered the secret to eternal youth: be born a turtle. Two studies published in the journal Science on Thursday revealed scant evidence of aging among certain cold-blooded species, challenging a theory of evolution which holds that senescence, or gradual physical deterioration over time, is an inescapable fate. Although there have been eye-catching individual reports — such as that of Jonathan the Seychelles tortoise who turns 190 this year — these were considered anecdotal and the issue had not been studied systematically, Penn State wildlife ecologist …