I’ve been struck over the past year by just how tricky it is to conceive of important differences between individuals within the same species.
We have come to terms with the notion that beasts from octopuses and grouper fish, to crows, chickens and parrots, chimps, cows and horses can deceive, or feel pain, grief, terror and joy.
Advertisement
And we also recognise that there are individual species that show consistent differences in how they conduct themselves, from brave to shy, lazy to active, curious to phlegmatic, rambunctious to timid.
But beyond that there is a world of individual variation in how this behaviour manifests itself. For ethologists and zoologists this, is, at the very least, vastly inconvenient.
Ducks in a row
The reason is to do with methods. Any field-going ethologist, crouched behind binoculars and a handy tree, needs to know which box to tick when an animal behaves in a particular way. There are, after all, theories to test, and we need concrete definitions to get our cause-and-effect ducks properly lined up in a nice predictive sequence.
Animals having different characters makes the whole thing even fuzzier than it already is. Ending up with many classes means we can hit the problem of sample size: if it appears to be too small, a paper can be rejected no matter what other tasty innovations it might be bringing to ethology´s intellectual feast.
Squaring up the possible importance of noticing tiny variations against the need to publish is a big deal.
For example, in the wild, animals must make all sort of guesses and approximations. What used to be thought of as mistakes may, we now realise, be carefully calculated judgements based around trying to balance the risk of death against feeding time lost by deliberate cowering in the face of a predator.
Juggling animals
Animals are consummate option jugglers, and for many of them, even repose gets coopted for survival: they leave the foods that are hardest to digest till last, eating them only in the late afternoon, so they have the whole night to digest them.
Another area where it turns out that vital, minute variation needs to be logged is the way animals trade in energy and time. Just like a human short of cash, animals will moonlight – literally, in the case of some monkeys who forage at night as a way of supplementing their energy income.
But the newest discovery of all, when it comes to the big picture of variation and difference, is that we now know just how little we know. Nowhere is this truer than in the Amazon basin, where recent analyses of animal and plant distributions have shown two important new facts: first, that many species are far more restricted in their habitat preferences than we imagined, and second, that we´ve recorded them in far fewer places than we thought.
To complicate things, it also turns out that we´ve visited a lot less of the than we realised – so there are massive gaps in our knowledge. Whole river basins where scientists have never set foot (or, if they did, those responsible never published any papers, which amounts to the same thing).
Enter Alfred Russel Wallace, the British naturalist who independently conceived the theory of evolution, and largely founded the scientific study of animal distribution. The holes in our knowledge I’ve just outlined are, rather charmingly, known as Wallacean – and there are an awful lot of them in the Amazon. Ìý
So, as holiday planes fly over the Amazon, they´ll be passing over animals and plants we don´t yet know exist in places we´ve yet to visit. Perhaps during this coming year we’ll work out how to deal with the unfolding picture of minute and important difference and tiny sample sizes – because in this case, and as all good scientists have etched on their hearts, the devil really is in the detail.
