Brown Widow Vs Black Widow

About the episode

Not too big, long slender legs, black with an orange-red patch on its back: most people will recognize the spider called the black widow, even if you’ve never seen it in the wild before.

The spider is not aggressive, but it is very venomous, which has given it a rather fearsome reputation. Now it turns out that the spider itself also has something to be afraid of. Cousins ​​in their own family don’t seem to enjoy their company at all.

Researchers have noticed for some time that the black widow spider is giving way to the invasive brown widow spider in many places in Florida. The first thought was: apparently this brown species native to Africa is simply winning when it comes to food and habitat. But new research shows things are a little darker.

The brown widow actively pursues the black widow. They are 6.6 times more likely to kill a black widow spider than to kill another species of spider in the same family. While of all the species in the study, the black widow spider was the least aggressive: it only attacked to defend itself.

Incidentally, humans don’t have much to fear: towards us, both species are very shy. The brown widow spider bite is also less venomous and bites are very rare.

The brown widow’s aggressive behavior towards a specific family member is very remarkable, according to the researchers. Usually, one species trumps another by being bigger, stronger, more fertile, or more resilient. Attacking family members who are already present is not common. That’s why they now want to research the area where the Brown Widow is from. Does the spider also behave this way towards the family? Or is it a behavior that the animal only began to adopt when it arrived in America?

Read more about research here: Brown Widow Spiders’ Likely Aggressive Engine of Black Widow Decline.