Question: Does geographic distance between salamander populations increase their reproductive isolation? To answer this question, researchers studied populations of the dusky salamander (Desmognathus ochrophaeus) living on different mountain ranges in the southern Appalachian Mountains. The researchers tested the reproductive isolation of pairs of salamander populations by leaving one male and one female together and later checking the females for the presence of sperm. Four mating combinations were tested for each pair of populations (A and B)—two within the same population (female A with male A and female B with male B) and two between populations (female A with male B and female B with male A). The proportion of successful matings for each mating combination was measured. For example, when all the matings of a particular combination were successful, the researchers gave it a value of 1; when none of the matings were successful, they gave it a value of 0. Then the researchers calculated an index of reproductive isolation that ranged from 0 (no isolation) to 2 (full isolation). The reproductive isolation value for two populations is the sum of the proportion of successful matings of each type within populations (AA + BB) minus the sum of the proportion of successful matings of each type between populations (AB + BA).
The table (Figure 1) provides data for the geographic distances and reproductive isolation values for 27 pairs of dusky salamander populations.
Part A - Understanding experimental design
What hypothesis did the researchers test in this study?
Answer:
"Reproductive isolation increases with geographic distance between dusky salamander populations"
Explanation:
The mechanisms of reproductive isolation are a assemblage of evolutionary mechanisms, behaviors and physiological procedures dangerous for speciation. They avert followers of dissimilar types from manufacturing offspring, or confirm that any offspring are germ-free. While in allopatric speciation the reproductive isolation is resolute superficially by the spatial isolation of populations, during sympatric speciation specific groups of persons create distinct mating organizations with self-like persons while distribution the similar home with the rest of the unique inhabitants.
Answer:
Bacteria are essential in cycling the nutrients back into the soil for plants to use, and cycling nitrogen back into the atmosphere. Nitrogen is found everywhere in the world, including animal waste, the atmosphere, and decaying matter.
<u>Complete Question:</u>
Nutria, Myocastor coypus, are large, semi-aquatic rodents native to South America. They were originally introduced in the US in 1889 for their fur. When the nutria fur market collapsed in the 1940's, thousands of nutria were released into the wild by ranchers who could no longer afford to keep them. Characteristics of the nutria include of those here EXCEPT
A. their status changed from introduced to invasive.
B. nutria affect the natural food web of the marshes.
C. nutria inflict permanent damage to marshes and other wetlands
D. nutria can only live in freshwater marshes in coastal areas along the Gulf
Coast.
<u>Correct Option:</u>
The characteristics of the nutria include of those here EXCEPT that "nutria can only live in freshwater marshes in coastal areas along the Gulf Coast".
<u>Option: D</u>
<u>Explanation:</u>
Nutria survives not only in freshwater marshes but also in wetlands, and can respond to various environments reasonably easily. In aquatic habitats, the species flourish and migrate rapidly across rivers into coastal wetlands. Nutria harm prone ecosystems can be seen in many ways.
Beyond destroying plants and crops, nutria kills the channels of ditches, streams, and other water bodies. Even so, the irreversible harm that nutria can do to marshes and other wetlands is of utmost importance. Nutria in these places rely on native plants which hold together wetland soil. This vegetation's degradation exacerbated the depletion of coastal marshes caused by sea level rise.
53 percent of your genome.
