Evidence for Evolution: Cumulative Flashcards
[h]Evidence for Evolution Cumulative Flashcards
[i]These flashcards cover a lot of information. Work with them slowly and carefully, until you can recall the information at a high level of mastery. You don’t need word for word recall. Your goal is a fluent and confident response to each prompt.
[q]Evolution is a theory. From a scientific perspective, what does it mean that evolution is a theory, rather than a hypothesis?
[a]To say that evolution is a theory means that it’s an organized explanation that has been thoroughly tested and is well-supported by evidence. A hypothesis is an unproven idea or educated guess that needs further testing.
[q]Proving evolution to be true involves finding evidence of
[a]Proving evolution to be true involves finding evidence of descent with modification.
[q]List four examples of evolutionary change that have been directly observed by humans in recent times.
[a]Examples of evolutionary change that have been directly observed by humans in recent times include
- Changes leading to new variants in SARS-CoV-2.
- The peppered moth’s change in color from light to dark and back to light in response to environmental change in the forests of Northern England.
- Antibiotic resistance in bacteria, particularly the emergence of MRSA.
- Resistance to the pesticide DDT in mosquitoes.
[q]What are homologous traits? List examples.
[a]Homologous traits are structures that are inherited from a common ancestors. Examples include
- The forelimbs of vertebrates, which are all composed of the same bones
- Proteins such as hemoglobin and cytochrome c.
- Genes coding for eye development and body structure.
[q]What are vestigial traits? How are they evidence of evolution?
[a]A vestigial trait is a structure that has lost its function, and only remains in a reduced form. Vestigial traits are evidence for evolution because they’re examples of descent with modification. The only reason why a vestigial trait would exist is that the ancestor of the species with the vestigial trait had a functioning version of the trait.
[q]List three examples of vestigial traits.
[a]Note: many answers are possible. The vestigial traits introduced in this module included
- Reduced/non-functioning eyes in cave fish
- The coccyx (tail bone) and ear muscles of humans.
- The reduced leg bones of whales
[q]What are fossils, and how do they serve as evidence for evolution?
[a]Fossils are the petrified remains of any once-living thing from the past. They serve as evidence for evolution because
- They show that life has changed over time.
- Their placement in sedimentary strata confirms descent with modification in lineages such as vertebrates and plants. For example, in the fossil record fish precede amphibians, which precede reptiles, which precede birds and mammals.
- The existence of transitional fossils, which link ancestral groups with their descendants.
[q]What are the two ways of dating fossils?
[a]Fossils can be dated by
- Relative dating, which compares the age of fossils by their position in sedimentary strata
- Radiometric dating, which tells the age of a fossil based on the decay of radioactive isotopes in volcanic rocks in strata adjacent to where the fossil was found.
[q]What are analogous forms? List several examples.
[a]Analogous forms or structures are superficially similar forms that result from convergent evolution. Examples include
- The streamlined form of dolphins, sharks, and ichthyosaurs
- The beaks of a platypus and a duck.
- The wings of a bat and a bird.
[q]How does comparison of embryos provide evidence of evolution?
[a]Comparing embryos provides evidence of evolution for two reasons:
- A common pattern of embryonic development indicates descent from a common ancestor.
- Embryonic development often involves the appearance and disappearance of vestigial traits. This only makes sense if these traits were inherited from an ancestral species. For humans, two such embryonic traits include gill slits and a tail.
[q]List two examples of widely shared proteins. How are these molecules evidence for evolution?
[a]Two widely shared proteins are cytochrome c (used in cellular respiration) and hemoglobin (used to transport oxygen in red blood cells) These shared proteins are evidence for evolution because these molecules are homologous. The species that share them must have had a common ancestor.
[q]What are four homologous features shared by all eukaryotes indicating that they share a common ancestor?
[a]What are four homologous features shared by all eukaryotes that indicate common ancestry?
- Cells with mitochondria
- Complex cells with internal compartments like the E.R., Golgi apparatus, and lysosomes.
- A membrane-bound nucleus that separates chromosomes from the cytoplasm.
- Linear chromosomes.
[q]List six homologous features shared by all living things, and which indicate that all living things descend from a common ancestor.
[a]Six homologous features shared by all living things, and which indicate that all living things descend from a common ancestor include
- DNA as the genetic material
- A system where DNA is transcribed into RNA, which is translated into protein.
- Using ribosomes to synthesize protein.
- Being composed of cells
- Using ATP to power cellular work.
- Using the same genetic code
Evidence for Evolution: Cumulative Quiz
[h] Evidence for Evolution: Cumulative Quiz
[q multiple_choice=”true”] Evolution is a well-supported explanation of the living world, based on a body of facts that have been repeatedly confirmed through observation and experiment. That makes evolution a
[q] If evolution is true, then one should be able to provide evidence for descent with [hangman] in any specific lineage.
[q multiple_choice=”true”] The evolution of the peppered moth during the past 150 years has involved selection by predatory birds for
[q multiple_choice=”true”] Many observations of evolution in historical time provide evidence that evolution has occurred. Which of the following is NOT an example of evolution that’s been directly observed?
[q]The beaks below are modified forms of an ancestral structure in a common [hangman]. Therefore, we can say that they’re [hangman] structures.
[q]Structures in human beings like our tail bones or ear muscles are [hangman] structures. That means that they’re structures that have lost their [hangman].
[q multiple_choice=”true”] Fossils form in which of the following rock types?
[q]Dating a fossil based on its position within sedimentary strata is known as [hangman] dating. Dating a fossil based on the decay of radioactive isotopes in nearby volcanic rocks is known as [hangman] dating.
[q] Which layer from Montana below has fossils that are the same age at layer 3 in Texas?
[q multiple_choice=”true”] Isotope M has a half life of 10,000 years, during which it decays into isotope N. You’re studying a sample of material that has a relative proportion of 50% M and 50% N. How old is this material?
[q multiple_choice=”true”] In terms of evolution, the forearm of a human being and the flipper of a dolphin are best described as
[q] [hangman] traits results from shared ancestry. There is a similar underlying structure, but the [hangman] might be different. [hangman] traits result from [hangman] evolution. The function of the part might be similar, but the underlying structure is usually quite different.
[q] Embryos of humans show various [hangman] traits such as a tail or gill slits that are not present in the adult form. In addition, the common developmental pattern shown by these vertebrate embryos is evidence of [hangman] with [hangman] from a common ancestor.
[q multiple_choice=”true”] Proteins such as cytochrome c are widely shared. These proteins are _________, and indicate ____________.
[q multiple_choice=”true”]Which of the following is not a feature shared by all eukaryotes.
[q]The presence of DNA as the genetic material, transcription of DNA into RNA and translation of RNA into protein, and being composed of cells are traits found in all living things. These are [hangman] traits, and indicate that all living things are descended from a common [hangman].
- This ends this module on evidence for evolution. If you want to review, click the following link to return to the Evidence for Evolution (HS Level) Main Menu. Otherwise, choose a new topic from the menus above.