The answer is an embryonic stage. This is the period of gestation right after the implantation, this is when the major organs of a baby are formed.
In the embryonic stage, <span>ectoderm is the outer layer that develops to a hair, teeth, brain and spinal cord. </span>
The idea behind an available niche after extinction leading to speciation is: the fact that those species can grow distinct and then in other to survive develop new traits.
<h3>Meaning of speciation</h3>
Speciation can be defined as a process that births new species with different traits while they evolve.
Speciation occurs when extinction is eminent and most time in other to preserve that race they evolve into something new with new traits.
In conclusion, The idea behind an available niche after extinction leading to speciation is: the fact that those species can grow distinct and then in other to survive develop new traits.
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