Darwin & Natural Selection
This scientist is known for his work with natural selection, and he is known as the Father of Evolution.
Charles Darwin
Charles Darwin is best know for developing his theory of evolution based on his observation of what characteristic?
Darwin theorized that the finches on the Galapagos Islands were related because the finches
In any field of sunflowers, the height of the plants vary. Birds first eat the seeds from the tallest plants. If this eating pattern continues season after season, what would we expect to happen to sunflowers over time?
What event in history led to the the dark-colored peppered moth being better able to survive than the lighter-colored variety?
This is the process by which organisms acquire traits through sexual reproduction and/or mutation and then pass on these traits to the succeeding generations.
Biological Evolution
Prior to the time of Charles Darwin, it was widely believed that all organisms appeared on Earth at the same time and remained unchanged throughout history. Which of these proved to be the biggest influence in the development of this idea?
In addition to studying finches, Charles Darwin closely studied a group of land turtles that had become physically different because of
The blue-footed booby is a bird with, you guessed it, bright blue feet. During mating season, males display their feet to prospective females in showy dances.
This behavior has developed due to natural selection, since an effective dance helps to attract a mate and produce __________.
Monarch butterflies lay their eggs on milkweed plants and then the caterpillars eat the milkweed. The milkweed plant contains a toxin that is not poisonous to the caterpillars. When the caterpillars change into butterflies, the toxin in their systems make them poisonous to predators like birds so natural predators avoid eating the Monarch butterflies.
Viceroy butterflies look much like the Monarch. Because of this, they are saved from predators also. This protective mechanism is BEST called
This is the origin of a new species in evolution, there are many different methods by which this can occur. Different species cannot reproduce successfully.
Speciation
While on the Galapagos Islands, Darwin noticed that there were a number of species of finches that he theorized descended from a common ancestor. He hypothesized that these finches became isolated on an island and adapted to fit an ecological role on that island. What about the finches led Darwin to this belief?
All the finches Charles Darwin observed on the Galapagos Islands
The foundation for biological evolution or descent through modification is
Some scientists believe that many years ago, most life on Earth lived in water. Over time, some fish grew small legs and lungs that allowed them to come onto land. These fish MOST LIKELY did this because they
This is a biochemical process used for determining the order of the nucleotide bases, adenine, guanine, cytosine, and thymine, in any DNA molecule. By comparing the DNA sequence of two organisms, scientists can see if the organisms are related or not, as well as how closely they are related.
DNA sequencing
Darwin observed how farmers and breeders produced many kinds of farm animals and plants. These plants and animals had traits that were desired by the farmers and breeders. He also noticed how the study of similar body structures and vestigial organs could add to the evidence of evolution. After performing several breeding experiments, he came to certain conclusions and formulated some theories. His theory of evolution and natural selection is the most accepted one.
What is the reason behind the acceptance of Darwin's theory?
Charles Darwin was credited for writing the biological theory of __________________. The organisms that were used for the basis of his studies were ___________________.
The key difference between sexual and natural selection is that natural selection acts on traits which increase fitness, whereas sexual selection favors any adaptation which enhances mating success. Differentiate between the two by choosing the example of sexual selection.
On his visit to the Galapagos Islands, Charles Darwin discovered several species of finches that varied from island to island, which helped him to develop his theory of natural selection. It is believed that all of these species had one common ancestor and, over time, evolved into different species. After the burst of speciation in the Galapagos, a total of 14 species would exist: three species of ground-dwelling seed-eaters; three others living on cactuses and eating seeds; one living in trees and eating seeds; and 7 species of tree-dwelling insect-eaters. The finches varied mainly in the size and shape of their beaks. What statement BEST describes the speciation of the different finch species?
This describes the evolution of many diverse species adapted to their specific habitats but having one common ancestor. This usually occurs when the original species is separated from each other completely, such as geographic isolation. When this occurs, the organisms adapt to different resources, leading to a new species.
Adaptive Radiation
Darwin's finches are an example of adaptive radiation, the evolution of an animal or plant group into different types adapted to specialized ways of life. Their common ancestor arrived on the Galapagos about two million years ago. Over time, Darwin's finches have evolved into 15 recognized species differing in body size, beak shape, song and feeding behavior. The picture here shows finches with four different types of beaks. What statement best represents how one species of finches became many?
The following describes a lab on natural selection.
The materials needed for this lab included a bowl of toothpicks, a bowl of dried macaroni, a spoon, forceps, a binder clip, scissors, a plastic cup, and a timing device. The procedure for this lab was performed as follows: the number of toothpicks able to be consumed (picked up and placed into the cup) in a 30-second period by the spoon was recorded. The trial was repeated three times, then the spoon’s ability to consume macaroni for 30 seconds was recorded for the three trials. This procedure was repeated with the forceps, the binder clip, and scissors to represent each bird's beak. Averages were calculated for each beak’s ability to consume each food item.
What are the possible conclusions or outcomes one could reach from this experiment? (Choose 3)
Selective breeding, also known as artificial selection, is a process used by humans to develop species with desirable characteristics. In natural selection, the environment “selects” organisms with desirable traits to survive and reproduce, passing along the favorable traits. In selective breeding, humans choose organisms with desired traits to reproduce, passing these traits on to their offspring. Humans have been breeding plants and animals for specific, desirable traits for thousands of years. A labradoodle is a cross between a standard poodle and a Labrador retriever. The first official labradoodle dog was bred in 1989. They are bred for the desirable traits of both of the parent breeds, such as the lack of shedding of the poodle and the temperament of the Labrador.
What are some other examples of selective breeding? Choose all THREE that apply.
Antibiotics, such as penicillin, are drugs that kill or prevent the growth of bacteria. When antibiotics were first discovered, they seemed to represent a miracle cure for human diseases like pneumonia, typhoid, bubonic plague, and gonorrhea. Today there are resistant strains of bacteria that cannot be killed by antibiotics.
Can you pick out the statements that accurately describe the development of antibiotic resistance? (Choose 3)