I know this sounds silly but I just took the test they were made in the stars or B
Ok this might not be the best answer but just by reading it, it may be unreliable because numbers do change over time
Because they each get half their dna from both parents. in pea plants for example the offspring have a total of 14 chromosomes thus inheriting 7 from each parent. plus genetic mutation is always a possibility making the offspring genetically different from the parents.<span />
The ancestors of birds were most likely arboreal.
<span>Having gliding surfaces is advantageous in arboreal animals because it means less likelihood of dying due to a fall. You'll notice that plenty of arboreal animals today have gliding surfaces. </span>
<span>In the ancestors of birds, the gliding surface just happened to stretch from the "fingers" down to the body, setting up for control of the glide, and for further refinement with elongation of the fingers and arms. With this, the animals were not just saving their lives when falling, they could glide from one tree to another to look for food. </span>
<span>A similar process likely happened in the ancestors of bats. </span>
<span>Don't ask me about pterosaurs or insects, 'cause I don't know.</span>
