Fig. 142 A) In frogs, females are more attracted to males with long advertisement calls (LC) versus short advertisement calls (SC). Using in-vitro fertilization, researchers fertilized female eggs with sperm from either LC males or SC males. The quality of offspring from LC and SC sperm were then tested by metrics of fitness (growth, survival, etc).
B) In widowbirds, females are attracted to males with elaborately long tail feathers. Researchers artifically altered the length of male tail feathers (shortening or elongating them) and tested the likelihood that the males in each conditoin would be captured by a predator.
With new changes:
Fig. 142 A) In frogs, females are more attracted to males with long advertisement calls (LC) versus short advertisement calls (SC). Using in-vitro fertilization, researchers fertilized female eggs with sperm from either LC males or SC males. The quality of offspring from LC and SC sperm was then tested by metrics of fitness (growth, survival, etc).
B) In widowbirds, females are attracted to males with elaborately long tail feathers. Researchers artificially altered the length of male tail feathers (shortening or elongating them) and tested the likelihood that the males in each condition would be captured by a predator.
Fig. 142 A) In frogs, females are more attracted to males with long advertisement calls (LC) versus short advertisement calls (SC). Using in-vitro fertilization, researchers fertilized female eggs with sperm from either LC males or SC males. The quality of offspring from LC and SC sperm were then tested by metrics of fitness (growth, survival, etc). B) In widowbirds, females are attracted to males with elaborately long tail feathers. Researchers artifically altered the length of male tail feathers (shortening or elongating them) and tested the likelihood that the males in each conditoin would be captured by a predator.
With new changes: Fig. 142 A) In frogs, females are more attracted to males with long advertisement calls (LC) versus short advertisement calls (SC). Using in-vitro fertilization, researchers fertilized female eggs with sperm from either LC males or SC males. The quality of offspring from LC and SC sperm was then tested by metrics of fitness (growth, survival, etc). B) In widowbirds, females are attracted to males with elaborately long tail feathers. Researchers artificially altered the length of male tail feathers (shortening or elongating them) and tested the likelihood that the males in each condition would be captured by a predator.