Some organisms, such as fish and mosquitoes, produce very large numbers of offspring. According to the theory of natural selection, why is producing a large number of offspring essential?

producing a large number of offspring tend to make a relatively small energy investment in each other and don't usually provide much parental care.

when the displaced particles are perpendicular to the direction the wave travels, is called a transverse wave, whereas in longitudinal wave the displace practices are parallel to the direction of the wave.

in the given image:

first image shows - longitudinal wave

second image shows - transverse wave

third image shows - longitudinal wave

fourth image shows - longitudinal wave