Houseflies have very tiny hind wings that are too small to lift them off the ground. Scientists have observed fossils of an ancient insect they believe is related to houseflies. However, these insects had second pair of wings that were much bigger.

every el niño cycle is different. every year.

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.

scientists have discovered that hiv does not cause aids by the virus's direct effect on the host's immune cells, but rather through the cells' lethal influence on one another. researchers from the gladstone institutes have revealed that hiv does not cause aids by the virus's