Answer:
The Answer is A.
Explanation:
This is correct because evolution is a change in the inherited traits of a population over many generations. While natural selection is a mechanism where the members of a population best suited to their environment have the best chance of surviving to pass on their genes.
Plant has such a developed structure to protect they have cell wall which give it rigidity and structure and also have cellulose which provide strength
Answer:
True
Explanation:
The finches Darwin discovered are genetically different from other finches of the same species because of differences in habitat climate and the habitat itself.
Answer:
Species separated by a physical barrier for a long time, suffer allopatric speciation, so they can not interbreed anymore.
Explanation:
Allopatric speciation consists of the geographic separation of a continuous genetic background giving place to two or more new geographically isolated populations. These separations might be due to migration, extinction of geographically intermediate populations, or geological events. In this speciation, some barriers impede genetic interchange, or genetic flow, as the two new populations that are separated can not get together and mate anymore. These barriers might be geographical or ecological.
Vicariance is the geographical separation of an original population into two or more new groups. Discontinuities in the physical environment like rivers, mountains, water, etc., are physical barriers that impede genetic flow between the separated groups.
The process of allopatric speciation involves different steps:
- The emergence of the barrier.
- Interruption in the genetic interchange
- The occurrence of new mutations and their accumulation in time in each population. Slow and gradual differentiation.
- Genetic divergence by natural selection and reproductive isolation makes it impossible for the two groups to mate even if the barrier disappears.
- Prezigotic isolation mechanisms favored by selection once occurs a secondary contact between the new species in formation.
