In the wild, male house finches (carpodus mexicanus) vary considerably in the amount of red pigmentation in their head and throat feathers, with colors ranging from pale yellow to bright red. these colors come from carotenoid pigments that are found in the birds' diets; no vertebrates are known to synthesize carotenoid pigments. thus, the brighter red the male's feathers are, the more successful he has been at acquiring the red carotenoid pigment by his food-gathering efforts (all other factors being equal). during breeding season, one should expect female house finches to prefer to mate with males with the brightest red feathers. which of the following is true of this situation?

There is no short answer.

Explanation:

The example that is described in the question where the females choose their mates according to the color and brightness of the male house finch's feathers is an example of the natural selection processes named sexual selection and mate choice. They refer to situations where the female's or male's choice for mating depends on the physical traits of the other party which certainly indicates that their genes are favorable and healthy to produce offsprings with higher chances of survival.

Directional selection can also be a factor in this example, which indicates a situation where the phenotypes chosen by the female or male for mating purposes are the extremes of the spectrum. This can cause the dominant phenotypes to change over time, affecting the appearence of the species.

So therefore in this example, these theories can affect the choice of the female or the male in their decisions.

I hope this answer helps.

from almost the creation of the first true maps of the earth, people started seeing how continents would be able to fit together.   in particular, people noticed that south america fits almost exactly into africa.

you should be aware that while world maps were around early in the 1600’s and better defined by the end of the 1700’s, those maps were not ‘public’ but were treated as state secrets.   and so it was not till much later that the broader ‘science’ community had access to good quality and accurate world maps.

get the whole story here…

it is now known that most of the major continental masses can be fit together in a jigsaw process.   in fact we now know that the continents were indeed once all joined together as one land mass – the supercontinent of pangaea.

if you look at most world maps you will ponder how this is evidence, as the continents really don’t appear to ‘fit’ together very well.   what you need to understand is that the vast majority of maps are drawn using a map projection that has the north and south poles (which are points) are a line the width of the map at the top and bottom.   this means that the map distorts the true shape of the earth’s land and oceans as you love closer to the poles.     some other map projections distort less, but have the map shape looking like segments of an orange.   see here for a range of map projections.   check out the way greenland changes size in each!

what is more remarkable, is the next piece of evidence when added to the shape of continents.

location of mountains and fossils

what is remarkable, when you reassemble all the continents together, the ancient mountain ranges (many now eroded to their cores) and the location of rock types and fossils all match up.