Black-Widow Spiders

Do u know why some species of spiders r called Black-widow spiders? Coz the females usually eat the males after mating. In fact, many other animals eg female fireflies also devour males after mating. This sometimes happens unless if male have sense enough to scram quickly or offer another food supply for female.
This is why these females are larger than males.

Why such a carnivorous act? Coz they need proteins from males to produce good quality offsprings! The more nutritious the males, the healthier the offspriings.
Now the boys know how lucky they are to live in safety of male-dominated world! HUMPH!!!

Facts:

* Prey: insects
* Predator: Mud-Dauber wasps.
* The venom of the black widow spider is 15 times as toxic as the venom of the prairie rattlesnake.
* Only the female Black Widow is venomous; males and juveniles are harmless..
* Araneae is the Latin word for spider
* Black Widow spiders are not usually deadly, especially to adults, because they inject only a small amount of venom.
* The female Black Widow hangs belly upward and rarely leaves the web.
* The Black Widow is also called the “hourglass” or “shoe-button” spider.
* Black Widow is considered the most venomous spider in North America.

Genus: Latrodectus
Phylum: Arthropoda
Sub Phylum: Chelicerata
Class: Arachnida
Order: Araneae
Sub Order: Labidognatha
Family: Therididae
Species: 6
Source: http://www.desertusa.com/july97/du_bwindow.html