1. Anolis cristatellus and A. cooki are both trunk-ground anoles that live on Puerto Rico. A. cristatellus lives in a shady, forest environment, while A. cooki lives in an open, sunny environment. What is an adaptive explanation for why the dewlap of one species evolved to be brighter and that of another species darker?
The A. cristatellus has a brighter dewlap and the A. cristatellus has a darker dewlap since the dewlap is a piece of skin that male anole lizards uses to attract females. Dewlap color is an important trait involved in the speciation of anoles. This difference in dewlap color is due to the different environments that they live in. The A. cristatellus population lives in a shady, forest environment while the A. cooki population …show more content…
A dark dewlap is favorable in a sunny environment because it is easier to spot, therefore, males with darker dewlaps are more likely to mate and reproduce in a sunny environment. Dewlap color might influence mating behavior because female anoles tend to mate only with males with a certain dewlap color, which tells the females that they belong to the same species. A female will not mate with a male that has an unrecognizable dewlap color, which show that the male is from a different species. Different dewlaps keep different species from mating with one another, which means that it keeps different species reproductively isolated. If selection for a mate is based on the color of the dewlap, the result will be a disruptive selection in favor of both extreme phenotypes of very dark or very light because female anoles in sunny environments will more likely mate with males with dark dewlaps and females in dark environments will more likely mate with males with bright dewlaps. Additionally, selection for a mate based on the color of the dewlap causes reproductive isolation which will result in speciation. If an anole population …show more content…
cristatellus had an average dewlap color of 4.8 and A. cooki had an average of 2.5, which means that the brighter dewlaps are used in dark shady environments, such as the ones that A. cristatellus inhabit in, so females can easily see the dewlaps in spite of the environment. The A. cristatellus has a brighter dewlap by +2.3 and the A. cooki has a darker dewlap by -2.3. In comparison, lizards that want to stand out against the bright environment, such as those from the A. cooki species, will prefer a darker dewlap. This shows that dewlaps are an adaptation to the amount of light provided by the sun and dewlap color are allowing them to distinguish one another as well as to attract mates. During mating season, a lizard does not want to blend into the environment because it would miss its chance of finding a mate. Each species has its own dewlap color, therefore females will recognize the males of its own species and will only be attracted towards those who are in the same species. The possibility of two individual species interbreeding with each other and forming a population of a new species is low which makes them reproductively isolated. Since mating is based on dewlap color, those who are successful in finding a mate will pass on their genes and dewlap color to their offspring over time. Those who are unable to find a mate will eventually die off, and their dewlap trait will disappear with
The A. cristatellus has a brighter dewlap and the A. cristatellus has a darker dewlap since the dewlap is a piece of skin that male anole lizards uses to attract females. Dewlap color is an important trait involved in the speciation of anoles. This difference in dewlap color is due to the different environments that they live in. The A. cristatellus population lives in a shady, forest environment while the A. cooki population …show more content…
A dark dewlap is favorable in a sunny environment because it is easier to spot, therefore, males with darker dewlaps are more likely to mate and reproduce in a sunny environment. Dewlap color might influence mating behavior because female anoles tend to mate only with males with a certain dewlap color, which tells the females that they belong to the same species. A female will not mate with a male that has an unrecognizable dewlap color, which show that the male is from a different species. Different dewlaps keep different species from mating with one another, which means that it keeps different species reproductively isolated. If selection for a mate is based on the color of the dewlap, the result will be a disruptive selection in favor of both extreme phenotypes of very dark or very light because female anoles in sunny environments will more likely mate with males with dark dewlaps and females in dark environments will more likely mate with males with bright dewlaps. Additionally, selection for a mate based on the color of the dewlap causes reproductive isolation which will result in speciation. If an anole population …show more content…
cristatellus had an average dewlap color of 4.8 and A. cooki had an average of 2.5, which means that the brighter dewlaps are used in dark shady environments, such as the ones that A. cristatellus inhabit in, so females can easily see the dewlaps in spite of the environment. The A. cristatellus has a brighter dewlap by +2.3 and the A. cooki has a darker dewlap by -2.3. In comparison, lizards that want to stand out against the bright environment, such as those from the A. cooki species, will prefer a darker dewlap. This shows that dewlaps are an adaptation to the amount of light provided by the sun and dewlap color are allowing them to distinguish one another as well as to attract mates. During mating season, a lizard does not want to blend into the environment because it would miss its chance of finding a mate. Each species has its own dewlap color, therefore females will recognize the males of its own species and will only be attracted towards those who are in the same species. The possibility of two individual species interbreeding with each other and forming a population of a new species is low which makes them reproductively isolated. Since mating is based on dewlap color, those who are successful in finding a mate will pass on their genes and dewlap color to their offspring over time. Those who are unable to find a mate will eventually die off, and their dewlap trait will disappear with