Maybe they give the creeps to some of us, while others treasure them as pets: spiders are spread all over the world both in open nature and in our homes. There are thousands of species, some more venomous than others, to the point that they can kill a man in a matter of minutes. Despite their incredible diversity, all spiders create silk and design complex webs in which they catch their prey, nevertheless, silk is also great for climbing and laying eggs.
All spiders depend on their venom for survival: venom is the way to hunt and defend themselves, but from the many thousands species only about two hundred actually represent a threat for human health. The great thing about these creatures is that they have adapted to the harshest of environments from the desert and the tropics to the Arctic areas where they can live underwater.
In terms of gender relationships, male spiders are famous for being killed right after intercourse, or at least this is the general myth people know. Relatively smaller than the females, the male spiders of certain exotic species are indeed sacrificed for the perpetuation of their breed. Nevertheless, this is not a general rule as in most cases, both males and females survive the encounter.
Well adapted to various living conditions spiders use great camouflages, and they even imitate other species for survival. Most species have six or eight eyes disposed in various groupings on the body. Certain eyes are even more specialized than the others, not to mention the fact that there are also blind eye pairs that are located in various places on the articulate bodies of these creatures.
Webs are the distinct mark of spiders but even these have a particular imprint of their own: thus, some create sheet webs, others spiral webs, not to mention the true mazes that some dangerous species design as deadly traps for their prey. A clear example here is the distinct tangled web the black widow makes; yet, spiders also create webs for the protection of their nests. Placed above their “home” web, such silky defenses lower the vulnerability of spiders in front of aerial predators.
There are other spiders which do not depend on webs for survival, and one famous example of such a species is the giant tarantula. Though they can produce silk threads, they are however hunting their prey down by using the ambush method. Extremely venomous and dangerous, tarantulas often make great pets for spiders lovers. So, don't be surprised if you see such a hairy creature in a friend's aquarium.