Pheasants do not feed their chicks. Immediately after hatching, a...

Question

Pheasants do not feed their chicks. Immediately after hatching, a pheasant chick starts pecking at seeds and insects on the ground. How might a behavioral ecologist explain the ultimate cause of this behavior?
a. Pecking is an innate behavior.
b. Pheasants learned to peck, and their offspring inherited this behavior.
c. Pecking by newly hatched chicks is the result of trial-and-error learning.
d. Pecking is a result of imprinting during a sensitive period.

Accepted Answer

Hi everyone. Welcome back. Here's our question. It says the probability of paternity is higher when Well let's think about what probability of paternity means. And that would be the likelihood that a given male is the father of a given offspring or set of offspring. So we want to think about the situation in which the probability is the highest from the point of view of a particular male that he is the father of the offspring. So Choice A. Says egg laying and mating occurs separately. Well this would definitely not be our answer if the female releases eggs and then later on the mail comes along and releases sperm. There's no guarantee that there wasn't another male along earlier to fertilize the sperm. So this would give a lower probability of paternity when these two events occur separately. Choice B. Says fertilization is internal. Um This still wouldn't be our highest probability of paternity because the egg and the egg is released at a different time from the sperm being released. So the egg is released inside the female. Later on mating occurs, the sperm comes in but again there could be a chance that another male had made it with the female earlier. That's again, a separation of the release of the egg and the release of the sperm. So it won't give the highest probability of paternity. So not our answer choice C says fertilization is external. Well yes this would be our answer because external fertilization with egg release and sperm release happening at the same time is the highest probability of paternity since they happen at the same time that male sperm obviously that have the highest probability of being the ones to fertilize those eggs. And as a result we see in this case with external fertilization um We see males more likely to be caretakers of the eggs and offspring because they know they have a higher percentage chance of this being their offspring. So they're more likely to invest time and energy in caring for the offspring. So you see this example in various kinds of fish like the male jaw fish carries his eggs in his mouth. Um He spits them out and brings them back in to aerate them and protects them from predators. So he puts a significant investment into taking care of those eggs. And finally Choice D says reproduction is sexual. Um We're going to cross that out because that doesn't really make sense if reproduction has to be sexual um to have paternity. So that's not really doesn't mean anything. We're talking about what causes the probability fraternity to be higher. So again the probability of paternity is higher when Choice c fertilization is external. See you in the next video

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