1. during ecological succession, the first
organisms to enter an ecosystem for
reestablishment are called pioneer
species. two examples of organisms
that are pioneer species would
be
and

Twins are born minutes apart, not a year apart. fraternal twins are no more closely related genetically than ordinary siblings born a year apart. they just happen to be born at the same time. identical twins result from a single fertilized egg dividing and separating early in gestation. although identical twins are more similar to each other than other siblings, there is some research to suggest they are not 100% the same. you and your brother share very similar dna because you have the same parents, and you look the same. i'll bet you resemble one or both of your parents, and likely a grandparent or two as well.

1.989×10^30 kg is the weight of the sun.

The short-term effect of tar on the body is increased blood pressure.