How is natural selection and the flu connected?

Viruses undergo evolution and natural selection, just like cell-based life, and most of them evolve rapidly. When two viruses infect a cell at the same time, they may swap genetic material to make new, “mixed” viruses with unique properties. For example, flu strains can arise this way.

Can humans influence natural selection?

If climate change is caused by humans, then no organisms can avoid selection resulting from human actions. A well-known example of natural selection in action is the development of antibiotic resistance in microorganisms.

Are diseases part of nature?

They are a result of things people do to nature. Disease, it turns out, is largely an environmental issue. Sixty percent of emerging infectious diseases that affect humans are zoonotic — they originate in animals. And more than two-thirds of those originate in wildlife.

How does natural selection affect the spread of inherited diseases in human populations?

Searching for Patterns of Variation As genetic variants conferring resistance to infectious diseases spread through human populations over time through natural selection, they leave distinctive, detectable patterns of genetic variation in the human genome.

How can a disease affect an ecosystem?

Infectious diseases are a strong force that can affect individual organisms, populations, communities, and ecosystems. Infectious diseases are caused by parasites and pathogens which can impair or even kill its host. Surprisingly, parasites and pathogens are a common and integral part of healthy ecosystems.

What is the nature of a disease?

disease, any harmful deviation from the normal structural or functional state of an organism, generally associated with certain signs and symptoms and differing in nature from physical injury. A diseased organism commonly exhibits signs or symptoms indicative of its abnormal state.

What are the conditions for natural selection to occur?

For natural selection to occur there must be genetic differences among the individuals of an interbreeding population of organisms. Consider what happens in a population of genetically identical organisms.

Is there a correlation between genes under negative selection and disease?

The authors also found a correlation between genes predicted to be under negative selection and genes implicated in certain hereditary diseases.

How did human migration affect the evolution of pathogens?

As humans migrated throughout the world, populations encountered distinct pathogens, and natural selection increased the prevalence of alleles that are advantageous in the new ecosystems in both host and pathogens.

Does positive Darwinian natural selection increase evolution?

The study suggests that positive Darwinian natural selection — in which some forms of a gene are favored because they increase the probability of survival or reproduction — is responsible for the increased rate of evolution.