According to evolution, two gases that probably existed in earths early atmosphere

Which sentence best expresses the differing opinions of these two book reviews?

Apea plant that is heterozygous for the tall phenotype can produce short offspring when self pollinating. which of the following explains why this occurs? a. segregation of allels b. condominance of traits c. polygenic expression of traits d. independent assortment of alleles

Environmental differences within ecosystems are generally caused by