Answer:
The structure of their noses.
Explanation:
Catarrhines are distinguished from platyrrhines by several traits but the main distinctive feature between them, is the structure of their noses. This forms the basis of their names.
Platyrrhines are characterized by laterally-placed, rounded nostrils or flat-nosed while catarrhines have narrow, downward-facing nostrils or hooked-nosed.
Another distinguishing feature include their dental formulation which is 2.1.2.3 in catarrhines and 2.1.3.3 in platyrrhines.
The skull structure of catarrhines have frontal bone which make contact with the sphenoid bone unlike the platyrrhines.
Generally, catarrhines are much bigger in size than platyrrhines.
some of the special structures in the members of these phylum as follows:
Members of porifera are sponges. they have collar cells and cellular -level body organization. Cnidarian have stinging cells present on the tentacles around the mouth. Ctenophorans have comb-like plate cells for swimming. Platyhelminthes - members are first to have sensory and nervous tissue in the head region.
Answer:
Darwin observed marine fossils in the mountains and the uplift of land by an earthquake which supports Lyell's theory.
Explanation:
- Lyell's theory of an ancient Earth states "the formation of Earth's crust took place through countless small changes occurring over vast periods of time".
- So Darwin had an observation of marine fossils that uplifted the land through many years by earthquake. Which was the same thing Lyell's explained.
- According to known natural laws, It takes lots of time to form the earth's crust.