Overproduction
Most species produce more offspring than can survive.
Competition
Since living space and food are limited, organisms must compete for the necessities.
Variation
Differences between individuals in a population.
Adaptations
Any kind of inherited trait that improves an organism's chances of survival.
Natural selection
The environment selects organisms with optimal traits to be the parents of the next generation.
Speciation
Over many generations, favorable adaptations accumulate and may result in a new species.
It is caused by the atmosphere of the Earth. It is due of the scattering of light by the atmosphere. When the moon is near the horizon, the moonlight must pass through much more atmosphere than when the moon is directly overhead.
<span>The correct answer is b. Option a is incorrect because these models can demonstrate scientific theories, but they don't prove scientific theories (you would need experiments for that). Option c is incorrect because the models aren't always representing something abstract (i.e. DNA is very real, just very small). Option d is incorrect because they don't precisely mimic something in nature, but instead help us visualize something in nature that is difficult to see or comprehend.</span>
Answer:
Homologous structures can be described as the structures which are similar to one another present in different organisms. These similarities depict that the organisms might have a common ancestor i the past. For example, the forelimb of man, birds, dogs.
Analogous structures can be described as structures in different organisms which perform the same function but might not have a common origin. For example, the wings of bats and birds.
