El huevo amniótico de reptiles y aves está rodeado por una cáscara externa resistente que protege al huevo de los depredadores, patógenos, daños y secado.
Gradual changes in the frequency of diseases over long periods are known as SECULAR TIME TRENDS. For example, the rate of mortality in USA due to coronary heart diseases over a period of time. Onset of puberty in girls is also a secular time trend.
Secular time trend is also referred as Secular Variation and Secular Drift.
Answer:
In the cardinals, if the females start using a different criterion than the color of the feather when they choose couple, most likely to happen is that decreased variation in the shades of red because no form of the trait is advantageous.
Explanation:
Options for this question are:
- <em>Increased variation in the shades of red because the selection pressure has been relieved.</em>
- <em>Increased variation in the shades of red because the cardinals try different ways to impress the females.</em>
- <em>Decreased variation in the shades of red because no form of the trait is advantageous.</em>
- <em>Decreased variation in the shades of red because the only reason for variation was selection pressure.</em>
In the context of natural selection, male cardinals court females using the coloring of their feathers as a form of sexual selection. This means that the shades of red in the feathers are a selection criterion in these birds, and the more visible shades represent an advantage.
But, if the selection criterion was not the color of the feathers, this trait would no longer represent an advantage in the competition between the males to be chosen as a mate. Instead, the trait that would determine sexual selection would be the one that experiences an increase in its variation<em>.</em>
The reaction to produce soap can be completed by cooking animal fat with a very strong solution of SODIUM HYDROXIDE.
This process is called saponification. Chemically, animal fat and strong solution of sodium hydroxide or potassium hydroxide mixed together to produce soap and glycerol.<span />
Answer:
D.
The zone has very few mammalian species that compete for the fish.
Explanation:
The zone has very few mammalian species that compete for the fish is the significance that the temperate zone have on commercial fishing.