1. Non random mating
In genetic equilibrium individuals must mate at random. However, in many species, individuals select mates based on heritable traits, such as size, strength, or coloration, a practice known as sexual selection.
2. Small population size
Genetic drift does not have major effects on large populations but can affect small populations. Thus evolutionary change due to genetic drift happens more easily in small populations.
<span>3. Immigration or Emigration
Individuals who join a populations may introduce new alleles into the gene pool. Likewise individuals who leave may remove alleles from the gene pool. Any movement of individuals into (immigration) or out of (emigration) a population can disrupt genetic equilibrium, a process know as gene flow.
4. Mutations
Individuals who join a populations may introduce new alleles into the gene pool. Likewise individuals who leave may remove alleles from the gene pool. Any movement of individuals into (immigration) or out of (emigration) a population can disrupt genetic equilibrium, a process know as gene flow.
5. Natural Selection
if different genotypes have different fitness, genetic equilibrium will be disrupted, and evolution will occur.</span>
Plants and animals live in interacting, interwined communities. There is a characteristic set of species in different environments. For example, certain species of trees, shrubs, ground cover, arthropods, reptiles, mammals, birds etc. live in a temperate forest environment. A completely different set of creatures live in a marsh, or a grassland or an agroecosystem. However, the relationships between these groups can be defined by the ecological role they play, the flow of energy between them and the cycling of nutrients between them. This is a fancy way of saying "everything is connected"! And if you change one part of the system, something else changes. In an ecosystem management decision, you hope you know what those consequences of your actions are!) This is important in managing agroecosystems as well.
Due to the fact that the white blood cells can change their shape and squeeze in through smaller parts of the blood flow, they have the ability to protect the immune system from any infections. They able to move easily in the blood flow, meaning that they can stop any infections or illnesses that would have came the person's way. This is why a person that has more white cells is not ill that often because there are more cells able to reach that particular place of infection.
Muscles allow you to move your limbs.
