Why some aggressive some docile?

[Paul Arnold]

Does anyone have any thoughts or theories on this? All Tarantulas suffer from predation in the wild,perhaps some more than others? Is there a link between how a Tarantula defends itself from a predator,levels and frequencey of predation and the alledged docile/aggressive nature of some Tarantulas? For example, in captivity, G.Rosea can be coaxed very easily into a plastic container when its time for cleaning,without any sign of aggression (my experience only) whereas S.Calceatum displays nothing but aggression. Hmmm its a little hard to explain what im trying to get it. If its not personality or character,then why and what is the need for a Tarantula to be so aggressive/docile? Why can we approach some Tarantulas with an alledged little risk of being bitten and others not? Do,what we consider to be docile Tarantulas,use flight instead of fight in the wild to escape predators and this is why they never show aggression? Ha, I've just realised that theory has gone out the window as S.calceatum could easily leg it but chooses instead to stand its ground <puts head in hands,baffled again>

[James Box]

Does anyone have any thoughts or theories on this? All Tarantulas suffer from predation in the wild,perhaps some more than others? Is there a link between how a Tarantula defends itself from a predator,levels and frequencey of predation and the alledged docile/aggressive nature of some Tarantulas? For example, in captivity, G.Rosea can be coaxed very easily into a plastic container when its time for cleaning,without any sign of aggression (my experience only) whereas S.Calceatum displays nothing but aggression. Hmmm its a little hard to explain what im trying to get it. If its not personality or character,then why and what is the need for a Tarantula to be so aggressive/docile? Why can we approach some Tarantulas with an alledged little risk of being bitten and others not? Do,what we consider to be docile Tarantulas,use flight instead of fight in the wild to escape predators and this is why they never show aggression? Ha, I've just realised that theory has gone out the window as S.calceatum could easily leg it but chooses instead to stand its ground <puts head in hands,baffled again>

it's a mystery, to be sure. i would assume that some of the more docile T's are generally ones with nasty urticating hair that, through the long process of evolution, has been so successful that the behaviour has become lazy or docile, in some cases. let's be honest, if something wanted to eat you, but realised you were covered in barbed, allergenic spikes that you could easily launch at it...well it'd learn to leave you alone pretty quick, and you'd not have to do anything to defend yourself. this wouldn't be a foolproof method, of course, as some predators adapt to resist such things, or by chance already are resistent.

so that would explain to me why some individuals exhibit a defensive behaviour, and why some don't, even in a given species...

other explanations may have to do with camouflage. if a spider's camouflage is REALLY good, then drawing attention to itself, except as a last ditch effort, is the last thing it'll do. it'll hunker down and make itself invisible. this behaviour would persist even in captivity, as it's not like the spider has good enough eyesight to realise it isn't camouflaged...or hopefully not, as that would make for a permanently stressed animal.

most of my defensive species have typically had a flight reaction to disturbance before any kind of threat display or attempt to bite, that includes H maculata, though i'm sure others have had a different experience with them.

I'd assume that most old world spiders rely on camouflage first, but then there's always flight if they're built for speed, or threat displays if they are slow. and of course these tendencies will overlap a bit with individuals, making flight or fight behaviour a little hard to predict.

also, despite the lack of urticating hairs, i had a very docile P lugardi once (she did get more skittish next moult though)...and also an A ezendami that i could tell was a darling, though i never pressed my luck.

i saw on (i think) Lost Land of the Jaguar, the spider guy scooped up a T blondi who was as docile a spider as any i've seen. in fact, the ONLY defensive thing was when the guy pointlessly used a net, and she kicked a cloud of hairs up. i think this was just because the net belonged to Ray Gabriel and he had to get it in at least one shot but yeah the spider just was keen to walk everywhere...didn't act at all like the striking hissing monsters most of us are familiar with

also, despite the lack of a proper "brain" in spiders, i'm sure lots of stuff contribute to a general "mood", which may mean that one day the spider "feels" like standing its ground, and other days "feels" like not bothering. i wouldn't rule this out, just because they don't use the same thinking structure we do...or at least not in the same way we do.

not sure that's helped at all, but that's just my tuppence!

[James Heeley]

Love that post james yea i think its important to realise that as vertebrates, humans couldn't even begin to understand the behavior or thought processes (if they have them) of invertebrates. I would love more than anything to train my OBT to make me coffee but its not going to happen theirs is a different world i guess