Spiders: Backyard Science (1978)

spiders and their webs can be seen in almost every backyard only a few spiders can harm us most spiders are helpful to man because they eat harmful insects spiders are found in many shapes sizes but all spiders are alike in certain ways a close look at some spiders will help us tell them from insects and other small animals a spider's body has two main parts a head and chest part and an abdomen most spiders have eight eyes the eyes are located on the upper part of a spider's head some spiders have large eyes and see very well spiders have two pedipalps the pedipalps are used for feeling and for holding food spiders have eight legs the legs are jointed like the rest of the spider's body the legs are covered with short hairs the legs end in tiny Claws by looking at the underside of this spider we can see its fangs a spider has two fangs its mouth is between the fangs the fangs are used to put poison into the small animals the spider catches and eats a spider breathes through small openings on the underside of its abdomen these are the openings for breathing on the spiders this spider is on its silk web near the tip of the abdomen are the spinettes with which the spider spins silk the silk is a liquid within the spider's body when it reaches the air it forms a silk thread a spider uses its back legs to help it spin its silk this spider has caught an insect it wraps it in silk from its spinettes the silk will keep the insect from getting away spun into a web this spider is waiting for an insect to fly into its web when a large grasshopper flies into the Web the spider first backs away but soon runs up to wrap the grasshopper in silk with its fangs it puts poison into the grasshopper then it digests the juices from the insect's body this is another kind of spiderweb it is shaped like a funnel let's see what happens when an insect lands on this kind of Web the spider has felt an insect hit its web and runs to attack it it tries to get poison into the insect finally the poison works the spider carries its prey down into its web other kinds of spiders do not build webs this spider Waits on a leaf it sees an aphid and pounces on it all spiders lay eggs this spider is holding on to a large egg sack it has made inside are the yellow eggs when the eggs hatch tiny spiders crawl about they look like small adults the poison of most spiders is too weak to hurt us but the poison of this black widow spider can make people very sick or even cause death a black widow is shiny black it has a red mark on its Underside spiders are small animals a spider's body has two main parts they have eight legs spiders spin silk with their spinettes they lay eggs the eggs hatch into young which are much like the adults spiders are helpful animal can be found in almost every backyard [Music]