TELOMERES
Tiny details can have huge impacts. Telomeres are minute structures that protect the ends of chromosomes from damage, rather like the plastic tips of shoelaces. The longer the telomere, the greater the protection. But telomeres shorten with age and in response to stress and illness. Pet African grey parrots housed alone, for example, develop shorter telomeres than those who get to socialise. And shorter telomeres mean more damage to the chromosomes – damage that can be passed onto offspring (see ‘Ageing parents provide flaws’ on p16).