The mechanisms of reproductive isolation prevent the reproduction of two individuals from different species. The prezygotic mechanisms disrupt the stages of reproduction before the forming of the zygote or prevent the mating at the start, and the postzygotic mechanisms affect the stages of reproduction after the forming of the zygote.
So, the first and the third example (the urchins and the grasshoppers) show the prezygotic mechanism, as the two individuals are not able to mate or form a zygote.
The second and the fourth example ( zonkey and the death of a zygote) show the working of the postzygotic mechanisms, as the zygote is formed, but it seems to be inviable, and the zonkeys are sterile, preventing the individual to reproduce.
The normal, or emmetropic, eye accommodates properly.
Answer:
Big mammals as bears or Mammoths.
Explanation:
Neanderthal had a diet based in different food, for example, there are some evidence that they were feed on nuts, mushroom, and moss. The quantity of veggies were different depending the season and the region of the planet the neanderthals were. Of course, most of their diet were based in meat, basically of big animals because the evidence is that they had a digestive system appropriate to eat lean protein.
Studies of the bones and the coprolites showed a ratio of different elements as nitrogen and carbon, the ratio of the heavier element to the lighter, show the relationship among the meat/vegetable diet.
Hope this info is useful.
Answer:
Cancer is unchecked cell growth. Mutations in genes can cause cancer by accelerating cell division rates or inhibiting normal controls on the system, such as cell cycle arrest or programmed cell death. As a mass of cancerous cells grows, it can develop into a tumor.
