Brown Widow vs. Black Widow

about the episode

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

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

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

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

By the way, humans have little to fear: both species are very shy towards us. The brown widow’s bite is also less toxic and biting incidents are rare.

According to the researchers, the aggressive behavior of the brown widow towards a specific family member is quite remarkable. One species usually wins out over another by being larger, stronger, more fertile, or more resilient. It is not uncommon to attack family members who are already there. That’s why they now want to do research in the area where the brown widow comes from. Does the spider also behave this way towards the family? Or is it a behavior that the animal only began to use upon its arrival in America?

Read more about the search here: The aggressive drive of brown widow spiders is likely to be the decline of the black widow.