Evolution

simulate the conditions of early Earth and test whether organic molecules could be formed from inorganic compounds. The experiment produced amino acids, which are the building blocks of proteins, demonstrating that the basic components of life could have originated from non-living matter under early Earth conditions.

This process is known as natural selection, where individuals with advantageous traits are more likely to survive and reproduce, leading to the passing on of those traits to the next generation. Over time, this can result in the overall population having more of these beneficial traits.

Physical appearance, behavior, and specific skills are traits that humans often select for in breeding programs or domestication processes rather than relying on natural selection. This can lead to a rapid change in these traits over generations due to intentional selection pressures imposed by humans.

Ice cores drilled through the thickest glaciers at Earth's poles show the layers of snow that were deposited each season kind of like tree rings. The deepest layer in the deepest ice core is the oldest and in Antarctic, continuous ice cores date back at least 750,000 years.

Gases and particles of dust trapped in the snow forming the layers in the cores continuously preserves samples of the atmosphere and these can be analyzed to provide a record of the climate prevailing as each layer was deposited.

There is no evolution. Random mating, no immigration/emigration, or, in short, Hardy-Weinberg equilibrium holds.

Genetic variation is necessary for natural selection to occur. This variation provides the raw material for differential survival and reproduction, which drives the process of natural selection. Without genetic variation, there would be no differences for natural selection to act upon.

20/20 did a little test with men of various heights. They had a man that was only 5' 2'' in the line up. Women consistently said they would not consider him suitable mate material, even when 20/20's people said he was a doctor with some wealth. Women consistently, on average, mate with men about 2'' taller than they are. Height, when environmental conditions are controlled ( read food ) is a polygenic trait under influence of 5 to 7 genes. Natural selection, over time, has favored women who have a taller man in mind as a mate.

An adaptation is a change in structure or behavior that helps a living thing survive in its environment. It enhances the organism's ability to thrive and reproduce in its surroundings, increasing its chances of survival. Adaptations can result from genetic changes over time or through learning and behavioral modifications.

The Inuit people are often cited as an example of human adaptation to extreme cold environments. Over generations, their bodies have evolved to efficiently manage cold temperatures, including features such as shorter limbs, stockier builds, and increased metabolic rates. These adaptations have helped them thrive in the harsh Arctic climate.

There is strong and growing evidence that Archaea are the closest current example of the original form of life on Earth and it is thus possible that the origins of life on other planets may be found in similar organisms.

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The term archaebacteria is now considered outdated since in recent years it has come to be understood that Archaea and Bacteria share little and have long and distinct evolutionary backgrounds.

The Archaea are single-celled microorganisms with no cell nucleus or any other membrane-bound organelles. As such, the are highly simplified. The archaeal lineage may be the most ancient that exists on Earth.

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Nematocysts are specialized organelles found in the stinging cells of cnidarians. Their main functions are to inject toxins into prey or threats for defense and to aid in capturing and immobilizing prey using barbs or sticky threads.

Seals have a closed circulatory system with a four-chambered heart, similar to other mammals. This system allows for efficient oxygen distribution throughout the body and enables seals to thrive in their marine environment.

Let us say you have three alleles in a population of beetles. Two colors; brown is recessive to green. Thus you have; GG, which is homozygous dominant and green, you have Gb, which is heterozygous and also green. Then you have bb, which is homozygous recessive. This is your population of beetles.

What do you think the allele frequency would be if GG, the homozygous dominant, either immigrated, or emigrated out of or into your population of beetles? Since the frequency of Gb and bb would necessarily go down statistically you would see more green morphologies and a change in genetic allele frequency. Assuming normal conditions.

The ones with worse resistance are less suited to suvival, and hence are selected against by being destroyed by antivirals more often.

When repeated, this means successively more and more of each generation is highly resistant, or that the reistsance is higher in each one. This is almost exactly the definition of natural selection, replacing the general trait with the specific resistance to antivirals.

No, apes will not take over the earth unless their relationship to humans changes. The taking and keeping of control depends upon superior mental powers, physical force and technology. At this point, apes show no evidence of having or developing such advanced mental powers as mind control. They may be physically strong. But they lack the control that humans have over the physical environment. Neither do they seem to have the possibility of developing technology competitive with or superior to what humans have or are planning.

Genetic drift.

Yes, stabilizing selection favors average individuals by selecting against extreme phenotypes and maintaining the status quo. It arises when individuals with intermediate traits have a higher fitness compared to those with extreme traits, leading to a reduction in genetic variation over time.

Scientists believe that chemical evolution occurred around 4 billion years ago, shortly after Earth was formed. This process involved the formation of complex organic molecules from simpler compounds through reactions such as polymerization and the assembly of molecules on mineral surfaces.

Flying insects evolved by at least the Carboniferous period, around 350 million years ago. Some of the earliest flying insects were primitive forms such as dragonflies and mayflies, which developed wings for flight and became successful aerial species.

Effervescence due to the evolution of gas is typically caused by a chemical reaction that produces carbon dioxide gas. This gas forms bubbles that rise to the surface. Examples include the reaction of an acid with a carbonate or bicarbonate compound.

The legs of a cat and fins of a whale are analogous structures because they have different evolutionary origins but serve a similar function in terms of movement. Homologous structures would be when two species share a common ancestor and have similar structures with different functions.

Pedigrees help us understand how traits are passed because they are specfically bred to have a certain trait(s). This is usu. done by breeding two animals that look alike and breding their offspring to another look-alike animal/creature. Note that some pedigrees are "ruined" due to inbreeding (incest) resulting in occasional deformities or flaws.

Example

A purebred german shepherd should have two black moles on his/her cheeks together. If you bred two similar dogs you should have similar puppies. If you take another dog such as a traditional black and white border collie and bred it to a german shepherd, you can see how the puppies appear and what the differences are.

SOme traits are more desirable than others and offspring will be bred with another animal with desired traits. If this fails, normally the resulted offspring will be bred to the same creature or one similar to try and get the result. This is a result of what genes are reccesvie and which are dominate. The mroe you bred for something specific the more likely a gene is to become dominate.

It is believed by many that the archaea and bacteria developed separately from a common ancestor nearly 4 billion years ago.

both allowed the widespread dominance of organisms on land by preventing the embryo from drying out (thus decreasing dependance on a body of water) and provided protection and nourishment to the embryo.