The answer is D.<span>elliptical that is what a oval is called in other ways.</span>
The layer of the Earth's atmosphere where most planes fly is the stratosphere.
✔ A. Stratosphere
O B. Mesosphere
O C. Thermosphere
O D. Troposphere
If the isthmus formed gradually rather than suddenly, the morphological species, biological species, and phylogenetic species concepts.
<h3>
What is Isthmus genetical species?</h3>
The formation of the Isthmus of Panama, a slender land bridge that connects North and South America, caused the Pacific and Caribbean populations of marine organisms to split off about 3 million years ago. On both sides of the isthmus, different species of snapping shrimp have been studied. There appeared to be seven pairs of species, with one species of each pair being found in the Pacific and the other in the Caribbean, according to the morphological species concept.
The various species pairs inhabit slightly different ocean depths. These species pairs, which are divided by the isthmus, were indeed the closest relatives of one another, according to the researchers' estimates of phylogenies based on mitochondrial DNA sequences.
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