Which animals do play?
Two lectures in my animal behaviour class were devoted to animal play. But how to define “play” and how to know that animals are at play? Play is an energetically-demanding activity, occupying a considerable percentage of time in many a species’ life and it is not usually leading to food acquisition. While it is generally accepted that a playing animal is more at risk than a non-playing one (after all it makes itself more conspicuous; it can injure itself; it can even get lost), there must be some pay-off, some evolutionary benefit in addition to the simple enjoyment factor associated with play. —>—>
But to earwigs, centipedes and leeches it comes natural to be a good mother
Nobody would deny that it is a heart-warming experience to see how mothers devote themselves to their children. But it is even more touching to witness how some of the so-called “lowly creatures” look after their young like, for example, spiders (and my blog on the Jamaica red-back spider, also known as the Black Widow, has already been written, but not yet made public), but also earwigs, centipedes and leeches; how they protect, defend, feed and clean the little ones. —>
The famous British-Indian geneticist J.B.S. Haldane is often quoted to have said he was quite willing to die for two siblings and 8 cousins, a statement, which is of course based on genetic relatedness, later expounded mathematically by William D. Hamilton in his studies on kin selection. Altruism and putting oneself in danger to protect or save other individuals, usually closely related ones, is not confined to humans but actually widespread in animals. —>