Fossil Record
These preserved remains, impressions, tracks, burrows, and other traces of past organisms make up this type of evidence for evolution.
fossil record
A structure found in different organisms that is similar because it was inherited from a common ancestor is called this.
homologous structure
This molecule contains the genetic information used by organisms to develop and function.
DNA
This field studies where organisms live and how their geographic distributions have changed through time.
biogeography
Fossils show that organisms changed through time. DNA shows similarities between species. Anatomy shows shared structures. Biogeography shows geographic patterns. What larger scientific idea do all four lines of evidence support?
evolution/common ancestry
This type of fossil contains a combination of characteristics that helps scientists understand evolutionary relationships between different groups.
transitional fossil
Humans, bats, and whales all have a humerus, radius, ulna, wrist bones, and hand/finger bones in their forelimbs, even though these limbs perform different functions. These are examples of this
homologous structures
These are the four bases listed in the reading that make up DNA sequences.
adenine, thymine, cytosine, and guanine
When populations become separated geographically and experience different environments, food sources, predators, and habitats, this can decrease this process between the populations.
gene flow
A scientist discovers a fossil with characteristics of two different groups. Which station's evidence would this most directly belong to, and what would the fossil be called?
Fossil Record, and it would be a transitional fossil
This fossil organism lived about 150 million years ago and had feathers and wings like birds, but also teeth, clawed fingers, and a long bony tail.
Archaeopteryx
Modern whales have small pelvic and hind-limb bones inside their bodies even though they no longer use them to walk. These structures are examples of this.
vestigial structures
According to the reading, scientists generally expect species that have been evolving separately for longer periods of time to have more of these in their DNA.
differences
These closely related birds on the Galápagos Islands have different beak sizes, beak shapes, and feeding behaviors related to the food available on different islands.
Darwin's finches
A scientist discovers that two species have very similar DNA sequences. Which station would investigate this evidence, and what could the similarity suggest?
Molecular Biology, and the similarity could suggest that the species inherited the sequences from a common ancestor
Scientists find fossils showing that early members of this group had four functional legs and lived primarily on land, while later members became increasingly aquatic.
whales
A student says, "If a structure is vestigial, it must have absolutely no function." Based on the reading, why is this statement incorrect
vestigial means that a structure has been reduced or has lost most of its ancestral function, not necessarily that it has no function at all
Scientists use this type of diagram to represent hypotheses about evolutionary relationships. Species sharing a more recent common ancestor are generally placed closer together.
phylogenetic tree
This process occurs when one ancestral lineage gives rise to multiple populations or species adapted to different environments or ecological niches.
adaptive radiation
A scientist notices that the forelimbs of a whale, bat, and human have similar underlying bone arrangements despite having different functions. Which station investigates this evidence, and what are these structures called?
Anatomy and Embryology, and they are homologous structures
A student says, "The fossil record cannot be evidence for evolution because scientists haven't found every organism that ever lived." Explain why the student's reasoning is incorrect.
the fossil record is incomplete because fossilization is rare and fossils can be destroyed, buried, eroded, or difficult to find, but patterns across many fossils and geological layers still provide evidence of evolutionary change
Early embryos of different vertebrates develop structures associated with the head, spinal column, throat region, and tail. Scientists use these similarities as evidence because related organisms can share aspects of these structures.
comparative embryology
A student says, "Humans and chimpanzees are almost 99% identical, so that means humans evolved directly from chimpanzees." What is wrong with this conclusion?
humans and chimpanzees share a common ancestor; humans did not evolve directly from modern chimpanzees
During a severe drought on Daphne Major, small and soft seeds became less available while larger, harder seeds became relatively more important. Finches with deeper, larger beaks survived better, and the population's average beak size subsequently changed. What evolutionary process does this demonstrate?
natural selection
A population of organisms becomes isolated on an island. Over many generations, it becomes genetically and physically different from its mainland relatives. Which station investigates this pattern, and what evolutionary process may eventually occur?
Biogeography, and the populations may eventually undergo speciation