This falls in line with the current theory on the evolution of altruism, known as Hamilton’s Rule, which states that an organism will sacrifice to help another organism so long as they share enough genetic material. This rule was made famous by Richard Dawkins, but despite the rather cynical title of his seminal work – The Selfish Gene – incidents such as these squirrel adoptions are also a reminder of something rather wonderful: whatever its root genetic cause, altruism is hard-wired into animals and compassion is a natural state.
And, of course, these squirrel adoptions shed no light at all on the marvel of interspecies adoptions such as this case of the lioness in Kenya who repeatedly adopts orphaned oryxes or the gaggle of cat-adopting-squirrel stories such as this that populate Internet video sites. With ‘selfish’ genes playing no role in these adoptions, Gorrell can only theorize they are the result of females who become overwhelmed and confused by their hormones. Or, one could choose a more optimistic interpretation: kindness and compassion are such powerful forces that they eclipse all genetic considerations.