Photo Friday: Jumping Spiders (Eris militaris)

A wonderful thing happened yesterday: my labmate and fellow PhD candidate, Raphael, brought some of his research subjects by our lab, which meant I had live critters to photograph in winter, yay! 😀

Raph’s research focuses on behavioural syndromes in jumping spiders (Salticidae: Eris militaris). It’s hard not to anthropomorphize these little animals – their large eyes, colorful markings and complex body language make them wonderfully personable. They are, in fact, so darned adorable that I couldn’t get arachnophobe-ey around them even if I tried.

The large male was intense, bold and explorative – he was NOT a cooperative subject.  Also, he seemed more interested in showing off his impressive pedipalps than anything else:

Eris militaris male

The female was considerably calmer.  And, even though the male is strikingly marked with dark brown and bright ivory bars, I found her more subtle markings more beautiful.

Eris militaris female

Eris militaris female

Raph placed the male and female under separate petri dish lids, side by side. The female noticed the male. The busy male was too busy exploring to notice her…at least until the dishes were lifted. Then he launched into an impressive display of dance and posturing, tentatively approaching and touching the female – only to be rebuffed three times – until at last his efforts were rewarded with a receptive reply, and they coupled.

Spider sex (which I have never witnessed firsthand before) looks awfully complicated. Or uncomfortable. Or both.

Jumping spider sex. Hmm. Well that's interesting, isn't it?

Jumping spider sex - where the business is actually happening.

Jumping spider sex - the female looking...rather squashed.

I’ve invited Raph to tell us more about his research, and possibly show some of the videos he’s taken of his spiders (including the hilarious mating ritual that took place between the two subjects in the photos here!), so expect a guest post in the near future!