Answer:
because they both have jaws, lungs, and claws or nails and they include some of the same common ancestors.
Explanation:
In this kind of population, the make up of the population's gene pool will remain virtually the same as long as these conditions hold. In this kind of situation, no evolution can take place, all thing will remain the same. For evolution to occur, competition must exist.
Answer:
Density is nearly 3 cabs per hectare
Explanation:
Given -
There are three three intertidal regions.
Area of each intertidal region is
hectares.
Number of crab in the intertidal regions are as follows -
Intertidal region I - 7
Intertidal region I - 2
Intertidal region I - 6
Sum of crabs in all three regions is equal to

Total area of all three intertidal regions is equal to
hectares
Now density per hectare is equal to total population of crab divided by total area of all the three intertidal regions
Density 
Density is nearly 3 cabs per hectare
Answer:
Contraction.
Explanation:
Muscle tissues are defined as they are elastic and extensible in nature. In other words it's also defined as they are able to stretched and returned to its original size and shapes. A unique feature of muscle tissue is they are able of contractile in nature. With the help of this contraction they are able to sliding myosin and actin filaments which are present in muscles tissues.
Basically muscle tissues are three types:
1) Skeletal muscle: They are strong and rapid in contraction.
2) Cardiac muscle: They are strong in contraction.
3) Smooth muscle tissues: They are slow and weak in contraction.