V.I.S.T. and Natural Selection
The "V" in V.I.S.T. stands for this, the natural differences among individuals in a population.
What is variation?
One extreme trait becomes more common over time, such as black mice going from 1% to 95% of a population.
What is directional selection?
A human arm, a whale flipper, and a bat wing share the same bone structure. Structures like these are called this.
What are homologous structures?
In 1953 these two scientists used an electrical spark to model lightning on early Earth.
Who are Miller and Urey?
This is the term for the creation of a new species.
What is speciation?
Natural selection acts on this group, and it is the only thing that actually evolves over time.
What is a population?
Both extremes become more common while the average decreases, as when finches with large and small beaks increase and medium beaks decline.
What is disruptive selection?
On a cladogram with a fish, a human, and a chimpanzee, this organism is the human's closest relative.
What is the chimpanzee?
The Miller-Urey experiment produced these building blocks of proteins from inorganic gases.
What are amino acids?
Two populations separated by a river or a mountain range are experiencing this type of isolation.
What is geographic isolation?
This word describes how well an organism's traits match its environment, making it more likely to survive and reproduce.
What is fitness?
Human babies of average birth weight survive best, while very small and very large babies do not. This type favors the average.
What is stabilizing selection?
A cladogram does not show which animal is stronger or more evolved. A branching tree shows this about different species.
How closely related they are (their evolutionary relationships and common ancestry).
This gas was probably NOT present in the atmosphere of the primitive Earth.
What is oxygen?
Two populations are able to breed but differ in courtship songs or dances. This is the type of isolation.
What is behavioral isolation?
The mice on the lava rock did not decide to have black babies. Dark mice survived the owls and reproduced more. This process explains it.
What is natural selection?
In the owl lab, predators decided which dots survived. This term names the environmental force that determines which traits survive.
What is selection pressure?
If two species have very similar DNA sequences, they most likely share this.
What is a recent common ancestor?
This theory says that mitochondria and chloroplasts came from one cell living inside another cell.
What is endosymbiosis?
Members of two populations can no longer interbreed and produce fertile offspring. This is the type of isolation.
What is reproductive isolation?
The false idea that a giraffe stretches its neck and passes the longer neck to its babies is named after this scientist.
Who is Lamarck?
A drought leaves only large seeds, and large-beaked finches survive while small-beaked finches starve. Name the selection type and explain why average beak size grew.
Directional selection. Large-beaked birds survived, reproduced, and passed on the trait. Individual beaks did not grow from use.
A whale has a pelvis bone that does not help it swim but was used by an ancestor. A leftover structure like this is called this.
What is a vestigial structure?
Put these in the order they evolved: aerobic respiration, anaerobic respiration, photosynthesis.
Anaerobic, then photosynthetic, then aerobic.
Oceanic islands often have species found nowhere else because isolation limits this movement of genes between populations.
What is gene flow?
FINAL JEOPARDY: Putting It All Together. A student says, "The light mice realized they needed to be dark, so they changed color to survive the owls." Correct this using at least three of the four V.I.S.T. factors.
Variation already existed (dark and light mice). Owls selected against the light mice, so more dark mice survived and reproduced. Dark fur is inherited and passed on. Over time the population changed. Individual mice never changed color on purpose.