AB week9
Week 9- Parenting
Natural selection favors individuals with the highest reproductive success. As we discussed last week, successful reproduction depends on finding mates. As we'll discuss this week, successful reproduction also depends on producing offspring who survive to reproduce. key concepts: life history analysis, cost-benefit analysis, siblicide, brood parasites
Part 1
Write a respond to the information (150-200words)
Animals differ greatly in their parenting behaviors. Some animals provide the absolute minimum of care, simply depositing their eggs or sperm and then taking off. Other animals invest considerable time and energy caring for their young. When you think of doting parents, you probably think of birds and mammals, but other animals can be surprisingly caring ( fungus beetle , caymans, burying beetles ). This week we'll discuss a range of parenting behaviors. Before we start, let's see what your intuitions tells you about the costs and benefits of parental care. What factors do you think would influence the degree to which animals invest in caring for their young? Consider things like:
· the risk of predation to the parents and to the offspring,
· the likelihood of each parent mating again,
· the diet of the offspring and/or parents (how easy it is to obtain this food)
· whether the offspring demonstrate primarily instinctive or learned behaviors
· how long it takes offspring to mature
There are many factors involved, so each person should be able to contribute something new. If (and only if!) we exhaust that topic, you can also look up some examples of extreme animal parenting. Offer a specific ultimate explanation for the extreme behavior. That is, explain why natural selection would favor such behavior. Be sure to consider opportunity costs (what an animal sacrifices when it invests in parenting.)
http://www.bbc.com/earth/story/20150128-loving-beetle-tends-to-its-babies
https://www.youtube.com/watch?v=a25kikvEpOw
https://www.youtube.com/watch?v=Ua1wC59phpk
Use your own words and stick on those information and no other information. Don’t off topic.
Part 2- (Q1-6 MC +Q78 SQ)
https://video.nationalgeographic.com/video/00000144-0a43-d3cb-a96c-7b4f5e230000
1. Watch the video, Did this video give you another reason to think twice before swimming in the ocean?
Top of Form
A : yes, I'd rather not surround myself in sea urchin sperm
B : no, I don't mind
https://www.youtube.com/watch?v=tIOh_cIhmPQ
2. Watch the video, How does the cichlid father protect his young?
Top of Form
A : He hides them in rock crevices
B : He hides them in his mouth
C : He distracts predators by swimming away from his young
D : He nips at their sides
Bottom of Form
https://www.youtube.com/watch?v=eMYuapm-BgY
https://www.youtube.com/watch?v=7m8QlSPP7t0
3. Watch the video, According to the lifespan video, there is a sponge that can live
Top of Form
A : 200 years
B : 500 years
C : 1000 years
D : 10,000 years
https://www.youtube.com/watch?time_continue=7&v=wrMVtxEVXFg
4. Watch the video, How does menopause increase the reproductive success of orcas?
Top of Form
A : it reduces competition between the offspring of mothers and daughters
B : it allows them to have more young earlier in life
C : it benefits the species by reducing the percentage of birth defects.
Bottom of Form
https://www.youtube.com/watch?v=5aIzzMTbkuk
5. Watch the video, When do birds feed the chick that begs the most (rather than the largest chick)?
Top of Form
A : when the environment is predictable
B : when the environment is unpredictable
C : when the parent is inexperienced
D : when a predator is in the area
Bottom of Form
https://www.youtube.com/watch?v=4ArjlPAU_X4
6. Watch the video, Nasza boobies and Shoebills typically lay two eggs, but due to sibling rivalry they generally only raise one chick. What factor determines the chick that survives?
Top of Form
A : One chick is three days older and so gets a head start
B : Usually the chicks are different sex and the male dominates
C : Nothing. It's random.
Bottom of Form
7. Short question : Spotted hyena females often give birth to twins, and the pups compete aggressively for their mother’s milk. The battle between pups sometimes leads to the death of one of the twins. In some years, the mother hyena will intervene to stop the fighting between her offspring, and in some years she will not. From the standpoint of natural selection, her behavior is strategic. Why would the mother hyena's behavior vary in different years? Hint: the answer has nothing to do with the characteristics of the pups.
8. Top of Form
8. Short question Magpie newborns are fragile and may die from disease, hypothermia, etc. After a few days their survivability improves. Over that same time period, magpie parents change their willingness to endanger themselves to protect their young. Would you guess that parent risk-taking is positively or negatively correlated with nestling survivability? In other words, do you think the magpie parents will take greater risks for older or younger nestlings? Please explain your answer. Hint: Consider the costs and benefits for the parents' reproductive success. You can assume the cost of risk-taking doesn't change. How does the potential benefit of protecting the offspring change with the age of the offspring?
Bottom of Form
Part 3Bottom of Form
Use your own words, and stick on that information below, write around 200 words for the response.
One of the strangest parenting strategies used by animals is brood parasitism, which occurs in some birds and fish. Watch this video lecture on brood parasitism in cuckoos. https://www.youtube.com/watch?v=n0O6S4hDDfE
The video is long, but it is highly informative. (Feel free to skip the introduction by starting at 3:00. You might also skip the historical background by starting at 8:00. ) Then discuss these two questions using information and examples from the video. (1) If getting someone else to raise your young is an excellent way to increase reproductive success, why don't more birds do it? There are multiple reasons given in the video. (2) If raising someone else's young greatly reduces your reproductive success, why do the host parents go along with it? Obviously, cuckoos and their hosts have competing interests, how is this "arms race" playing out? As always, please make one point in your forum. This will allow others to easily contribute something new to the discussion. The video is pretty in-depth, so I think there should be enough material for everyone to add something.