Answer:
a) diversity
b) natural selection
c) living species
d) ancestral species
e) heritable variations in a population
f) greater reproductive success
g) an evolutionary adaptation
Darwin proposed a mechanism for evolution: natural selection, in which heritable traits that help organisms survive and reproduce become more common in a population over time.
See attached picture
Explanation:
Xenopus laevis is allotetraploid: it has 2 sets of homologous chromosomes originally from one species and 2 sets of homologous chromosomes originally from another species, making a total of 4 sets of chromosomes. During meiosis, every chromosome has another homologous one with which it can pair, producing viable gametes that have the complete genetic information of the species.
Mules, however, are allodiploid: they have one set of chromosomes from a donkey and another set from a horse, making a total of 2 sets of chromosmes. But those two sets are not homologous, so during meiosis the chromosomes can't pair and the gametes will have errors that make them inviable, making mules sterile
Prophase, metaphase, anaphase, and telophase.