Answer:
1. In allopatric speciation, a population isolated by a geographic barrier becomes a new species as it accumulates changes by natural selection or genetic drift.
2. In sympatric speciation, a new species may arise as mating and gene flow are reduced between populations that share the same area
3.Many plant species have formed by polyploid speciation, in which accidents in cell division result in extra sets of chromosomes.
4.Both allopatric speciation and sympatric speciation depend on the establishment of reproductive barriers, which prevent(s) gene flow between a new species and its parent species.
5.Adaptive radiation occurs when a species gives rise to many new species after colonizing a region with diverse habitats
Explanation:
The sentences 1-3 and 5 are the definitions of the terms in bold. Sentence 1 describes allopatric speciation; Sentence 2 describes sympatric speciation; Sentence 3 describes polyploid speciation; Sentence 5 describes adaptive radiation.
Regarding to sentence 4, reproductive barriers are essential to stop the genetic flow that could prevent speciation by genetically homogenizing populations.
