How have the historic levels of melanin in human populations changed due to migration? (1 point)
Responses
Humans that produced less melanin became more common as populations migrated away from the equator.
Humans that produced less melanin became more common as populations migrated away from the equator.
Humans that produced more melanin became more common as populations migrated away from the equator.
Humans that produced more melanin became more common as populations migrated away from the equator.
Humans that produced more melanin became more common as populations migrated toward the equator.
Humans that produced more melanin became more common as populations migrated toward the equator.
Humans that produced less melanin became more common as populations migrated toward the equator.
Humans that produced less melanin became more common as populations migrated toward the equator.
How would reducing low-growing plants from an area impact a population of tortoises with two varieties of neck extension ability: short and long distance?(1 point)
Responses
The variety of tortoises that could only extend their necks a short distance would go extinct.
The variety of tortoises that could only extend their necks a short distance would go extinct.
The proportion of tortoises that could only extend their necks a short distance would increase.
The proportion of tortoises that could only extend their necks a short distance would increase.
The variety of tortoises with the ability to extend their necks a long distance would go extinct.
The variety of tortoises with the ability to extend their necks a long distance would go extinct.
The proportion of tortoises with the ability to extend their necks a long distance would increase.
The proportion of tortoises with the ability to extend their necks a long distance would increase.
In an ecosystem, there are two color varieties within a species of toads: brown and green. Over 50 years, the proportion of the population that is green increases from 20% to 50%. Which statement is the most likely to explain this change? (1 point)
Responses
A disease caused a decrease in the proportion of brown toads.
A disease caused a decrease in the proportion of brown toads.
The environment changed such that toads that can jump higher into the trees to survive better.
The environment changed such that toads that can jump higher into the trees to survive better.
The environment changed such that green toads can blend into their surroundings better.
The environment changed such that green toads can blend into their surroundings better.
Pollution caused a decrease in the proportion of brown toads.
Pollution caused a decrease in the proportion of brown toads.
In an ecosystem where most flowers are long and bell-shaped, there are two varieties of hummingbird: birds with short beaks and birds with long beaks. What is the most likely hummingbird population composition? (1 point)
Responses
more short-beaked hummingbirds
more short-beaked hummingbirds
only short-beaked hummingbirds
only short-beaked hummingbirds
only long-beaked hummingbirds
only long-beaked hummingbirds
more long-beaked hummingbirds
more long-beaked hummingbirds
In an ecosystem, the average temperature increases, causing a shorter winter. There are two varieties of rabbits in this area, white-furred rabbits and brown-furred rabbits. Which scenario is most likely? (1 point)
Responses
The proportion of white-furred rabbits in the population increases.
The proportion of white-furred rabbits in the population increases.
Both white- and brown-furred rabbits decline.
Both white- and brown-furred rabbits decline.
The proportion of white-furred rabbits in the population declines.
The proportion of white-furred rabbits in the population declines.
Both white- and brown-furred rabbits increase.
Both white- and brown-furred rabbits increase.