When you combine the genotypes in the Punnet square you get :
1. EeRR
2.Eerr
3.EeRr
4.eerr
The ratio would be typical for a dihybrid cross: 9 of the individuals with both dominant traits, 3 of the individuals dominant for one trait, 3 dominant for the other trait and only one recessive for both traits.
There will be 9/16 of ebony flyes with red eyes
3-16 of ebony flies with orange eyes
3/16 of yellow flies with red eyes
1/16 of yellow flies with orange eyes
Bird migrations began with the recession of the glaciers during the ice age. You will notice a great increase in insects in the spring time and early summer.The birds moved North to take advantage of this increase in the food supply that followed the warming in the spring and early summer. Their reproductive organs temporarily developed so they could lay eggs and raise a family. Look at the early flush of Night crawlers in the moist times of the early rains. By mid summer most of the insects have matured, mated and died. Their eggs have hatched and turned to larva and moved underground until next spring. The shortening of the days causes the reproductive functions to decrease and signals the birds that the food will soon become scarce. They move back to the area that makes it the easiest to find food and avoid freezing. which of course is the warmer climates nearer the equator. Not all birds move past the Tropics at approximately 30 degrees. Some like Chickadees may move down from Mi or Mn or Canada only as far south as Indiana. Some migrations may be quite short. For example from the mountains down to the plains. They don't generally reproduce in the warmer winter climes they migrate to. In the spring time they migrate along paths of the retreating glaciers. As the climate warms away from the tropics the birds follow the emerging insects etc to the birds selected breeding grounds.with increased insects and longer days to feed the hatching's. It is necesary to understand why they move to cooler climates in the summer to under stand why they move to eh warmer ones in the fall. As the days shorten the food supply dwindles and the babies have fledged. They move to warmer climates in winter to rest and refuel for the next years migration.
The speed of light in a vacuum is 186,282 miles per second (299,792 kilometers per second), and in theory nothing can travel faster than light.
Laurentia<span> (</span>North American Craton<span>) is a large continental </span>craton<span> that forms the ancient geological core of the </span>North American<span> continent. Many times in its past, Laurentia has been a separate </span>continent<span> as it is now in the form of North America, although originally it also included the cratonic areas of </span>Greenland<span> and also the northwestern part of </span>Scotland, known as theHebridean Terrane<span>. During other times in its past, Laurentia has been part of larger continents and </span>supercontinents<span> and itself consists of many smaller </span>terranes<span> assembled on a network of Early </span>Proterozoic orogenic<span> belts. Small </span>microcontinents<span> and oceanic islands collided with and sutured onto the ever-growing Laurentia, and together formed the stable </span>Precambriancraton seen today.
Pond ecosystem considered as an open ecosystem because pond is always open . There is an interaction of pond with atmosphere , due to which it ecosystem becomes open.
