Which discovery could provide evidence against the theory of evolution?
The discovery of a primate and trilobite fossil in the same rock layer could provide evidence against the theory of evolution.
What type of evidence do scientists use to best explain how evolution has shaped Earth?
The fossil record provides evidence for the evolution of life on Earth, but scientists can also use fossils to determine how the environment of a region has changed over time.
Which idea inspired Charles Darwin’s theory of evolution?
Darwin was influenced by other early thinkers, including Lamarck, Lyell, and Malthus. He was also influenced by his knowledge of artificial selection. Wallace’s paper on evolution confirmed Darwin’s ideas. It also pushed him to publish his book, On the Origin of Species.
What is most likely happening to the genetic variation of the population of North East Arctic cod?
What is most likely happening to the genetic variation of the population of North East Arctic Cod? The genetic variation in the population is decreasing due to selective pressure.
What will happen to the frequency of the recessive allele?
What will happen to the frequency of the recessive allele for the HbS gene when there is an outbreak of malaria? The frequency will increase. For a gene with two possible alleles, if the frequency of the dominant allele is 0.75, what is the frequency of the recessive allele?
What is most likely happening to the genetic variation?
The genetic variation in the population is decreasing due to selective pressure. The genetic variation in the population is increasing due to gene flow.
How does genetic drift reduce heterozygosity?
Like the cheetah population, small populations that go through genetic drift are at risk for allele fixation, where one allele occurs at 100% frequency and the other allele is lost entirely. This results in a complete loss of heterozygotes. The effect of drift is indirectly proportional to the population size.
Why does genetic drift occur faster in small populations?
Drift is more pronounced in such populations, because smaller populations have less variation and, therefore, a lower ability to respond favorably — that is, adapt — to changing conditions.
What increases heterozygosity?
Remember that gene diversity is composed of two elements; 1) the number of alleles and 2) the abundance (or evenness) of the alleles. Both of these would increase the expected heterozygosity.
How is heterozygosity important?
Heterozygosity is of major interest to students of genetic variation in natural populations. It is often one of the first “parameters” that one presents in a data set. It can tell us a great deal about the structure and even history of a population. High heterozygosity means lots of genetic variability.
How do you determine heterozygosity?
HT= The average heterozygosity among organisms within the total area considered. This is calculated by taking the average of all the frequencies of the Adh-F allele, and then using 2pq to calculate an expected Total Heterozygosity.
Does inbreeding increase or decrease heterozygosity?
This results in mating among closely related individuals, such as brother–sister and parent–offspring mating. Inbreeding is a cumulative phenomenon and in the course of successive generations it increases homozygosity by 50% and reduces heterozygosity by 50% in F1, 25% in F2, 12.5% in F3, and 6.25% in F4.
What are the positive and negative effects of inbreeding?
Inbreeding results in homozygosity, which can increase the chances of offspring being affected by deleterious or recessive traits. Crossbreeding between populations also often has positive effects on fitness-related traits, but also sometimes leads to negative effects known as outbreeding depression.
Can we avoid inevitable inbreeding in animal populations?
Inbreeding due to genetic drift cannot be fully avoided because drift always occurs in a population. Mating related individuals increases homozygosity, and thus decreases genetic diversity.
Do lion prides inbred?
It has been also seen that when the dominant male is killed or driven off by one of the bachelor males, a father may be replaced by his son. So, inbreeding will occur. In the group (pride), most lionesses are related to one another as siblings, cousins, or nieces.
Do animals avoid inbreeding?
No, they don’t “know”. Each species has its own mechanisms to avoid inbreeding. Many are just not attracted to their kin, either by scent or by some psychological mechanism preventing them from feeling attraction towards siblings or other individuals they have grown with.
How many animals prevent inbreeding?
They created the “50/500” rule, which suggested that a minimum population size of 50 was necessary to combat inbreeding and a minimum of 500 individuals was needed to reduce genetic drift.