In a natural setting, all the eggs in a duck nest usually hatch within a few hours. Shortly after all the ducklings have hatched, and periodically thereafter, the mother duck will lead them all to a food source and then back to the nest to rest. Given this situation, which ducklings are most likely to imprint on their mother?

Question

• Only those that are less than 6 hrs old
• Only those that are over one day old
• Only those that are 10-18 hrs will successfully imprint.
• All ducklings will eventually imprint because of the repeated activity during the critical period

Answer 1

In the scenario described, the most likely answer would be:

All ducklings will eventually imprint because of the repeated activity during the critical period.

Imprinting is a rapid learning process that occurs during a critical period shortly after birth or hatching. In many bird species, including ducks, this critical period typically extends over several hours to days. Since the mother duck leads her ducklings to food and back to the nest, the repeated interactions and exposure during the critical period will likely result in imprinting for all of the ducklings, provided that they are healthy and able to follow her. The precise timing can vary, but they typically imprint on their mother shortly after hatching, and the repeated exposure supports this process.

Answer 2

Which animals have the closest evolutionary relationship, as shown by the cladogram? (1 point)
• humans and lampreys
• humans and trout
• humans and wallabies
• humans and lizards

Answer 3

To determine which animals have the closest evolutionary relationship according to a cladogram, we should consider their shared evolutionary history and common ancestors.

Among the options provided, humans and wallabies are likely to have the closest evolutionary relationship. Both humans (a type of mammal) and wallabies (marsupials) share a more recent common ancestor compared to the other options, which include more distantly related groups.

Here's a brief overview of the relationships:

• Humans and lampreys: Lampreys are jawless fish and diverged from the evolutionary line leading to humans quite early.
• Humans and trout: Trout are bony fish, and while humans and trout share a more recent common ancestor than humans and lampreys, they are still quite distantly related.
• Humans and lizards: Lizards are reptiles and diverged from the mammalian line long before the emergence of humans.
• Humans and wallabies: Both are mammals and share a more recent common ancestor than with any of the other groups listed.

So, the correct answer is humans and wallabies.