Brown anoles are lizards that live on islands in the Bahamas. They can have legs of different lengths.

Question

Lizards with shorter legs are better at climbing trees than lizards with longer legs. This makes lizards with shorter legs better at escaping from the floods that sometimes cover the islands.

The diagrams below show three possible lizard populations.

Diagram titled Population 1 containing a row of 8 lizard icons labeled Short Legs.
Diagram titled Population 2 containing 2 rows of 4 lizard icons each, one labeled Short Legs and one labeled Long Legs.
Diagram titled Population 3 containing a row of 8 lizard icons labeled Long Legs.
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10. If their environment changes so that there are many floods each year, which of the following lizard populations will most likely survive?
Responses

a
All the populations will survive because the lizards will change the length of their legs if they need to.
All the populations will survive because the lizards will change the length of their legs if they need to.

b
Populations 1 and 2 will most likely survive.
Populations 1 and 2 will most likely survive.

c
Populations 2 and 3 will most likely survive.
Populations 2 and 3 will most likely survive.

d
Only Population 2 will survive because it is the only population with variation.

Answer 1

The best answer is:

b. Populations 1 and 2 will most likely survive.

Here's why:

• Population 1 consists entirely of lizards with short legs, which are better at escaping floods due to their climbing ability.

• Population 2 has both short-legged and long-legged lizards. The presence of short-legged lizards means that some individuals will also be well-equipped to escape floods, while the longer-legged lizards may not be as suited for climbing.

• Population 3 consists entirely of long-legged lizards, which are not well-adapted to climbing trees and escaping floods. Thus, they are at a disadvantage in an environment with frequent flooding.

Therefore, both populations 1 and 2 have individuals that can survive, making option b the most accurate response.