Question

mechanisms of evolution guided reading
evolution is the change in the genetic make - up of a population over a period of time. evolution occurs at the population level. there are several mechanisms that can cause changes in a population that lead to evolution.
natural selection
natural selection, also known as survival of the fittest, is a key mechanism of evolution. natural selection is when organisms with favorable traits have a higher survival and reproduction rate than other members of their species. these favorable traits are known as adaptations.
a real - life example of natural selection is the rock pocket mouse. the rock pocket mouse can be found in the southwestern united states. ancestral pocket mice had light - colored fur coats that blended in with the rocks and sandy soil that were common in the region. this kept the mice hidden from their predators mainly owls. then, a series of volcanic eruptions spewed a river of black lava more than 40 miles long that wove right through the middle of pocket - mouse territory. lava flows created huge patches of dark rock among the surrounding light - colored sand.
today there are now two forms of pocket mice: light - colored mice that live on sandy soil and dark - colored mice that live on black lava rock. researchers noticed that rock pocket mice with a dark fur coat were more common on the dark lava flows, while the mice with light colored fur coat were more common on the light - colored sand.

1. evolution is the change in the ____________ make - up of a ____________ over time.
2. natural selection is when organisms with ______________ traits survive and reproduce more.
3. how has the rock pocket mouse adapted to survive in its environment? ______________
4. what color would you expect a rock pocket would to be that lives in lava flow area? ____________ why? ____________

genetic drift
genetic drift is the change in the genetic make - up of a population due to random chance. genetic drift occurs when a population is drastically reduced in size. this reduction in size may cause some traits to disappear completely and thereby reduce genetic variation. there are two major types of genetic drift: the bottleneck effect and the founder effect.
the bottleneck effect happens when the size of a population is severely reduced by events like natural disasters earthquakes, floods or fires, disease, or over - hunting.
for example, cheetahs face reduced genetic variation because their population size is decreasing due to over - hunting by humans and habitat destruction. cheetahs also have a low rate of reproductive success, meaning that as a species they are not always able to reproduce. with fewer offspring and less genetic variation the population can neither grow nor adapt to changes in the environment.
the founder effect is when a small group of individuals colonizes moves to a new area. the small population will contain a reduced amount of genetic variation from the original population which can result in

Explanation:

1. La evolución es el cambio en la composición genética de una población a lo largo del tiempo. Esto se extrae directamente del texto que dice "Evolution is the change in the genetic make - up of a population over a period of time".
2. La selección natural es cuando los organismos con rasgos favorables sobreviven y se reproducen más. El texto establece que "Natural selection is when organisms with favorable traits have a higher survival and reproduction rate than other members of their species".
3. El ratón de roca se ha adaptado desarrollando pelajes de colores que coinciden con su entorno. Los ratones con pelajes claros viven en suelos arenosos y los de pelaje oscuro en rocas de lava negra, lo que les ayuda a esconderse de los depredadores.
4. Se esperaría que un ratón de roca que viva en un área de flujo de lava sea de color oscuro. Esto se debe a que la selección natural ha favorecido a aquellos con pelajes oscuros que se mezclan mejor con el entorno de rocas de lava negra, lo que les da una mayor probabilidad de sobrevivir al evadir a los depredadores.

Answer:

1. genetic, population
2. favorable
3. Ha desarrollado pelajes de colores que coinciden con su entorno (pelajes claros en suelos arenosos y pelajes oscuros en rocas de lava negra) para esconderse de los depredadores.
4. De color oscuro. Porque la selección natural ha favorecido a aquellos con pelajes oscuros que se mezclan mejor con el entorno de rocas de lava negra, aumentando su probabilidad de supervivencia al evitar a los depredadores.