The answer is : friction.
<span>The “fossil record had caused Darwin more grief than joy. Nothing distressed him more than the Cambrian explosion, the coincident appearance of almost all complex organic designs,” according to Stephen Gould in the book entitled The Panda’s Thumb</span>
The density dependent factors<span> are </span>factors<span> whose effects on the size or growth of the population vary with the population </span>density<span>. There are many types of </span>density dependent<span> limiting </span>factors<span> such as; availability of food, predation, disease, and migration. However the main</span>factor<span> is the availability of food</span>
the cell cycle moves on the chromosomes thicken as the size of the cell grow and since became vissible!
The femur is the longest bone.