BIOL 180 Study Guide - Final Guide: Sampling Error, Species Richness

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crimsonraven456

17 Aug 2018

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Biology

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BIOL 180

Professor

John W Parks

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BIOL 180 Full Course Notes

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In the birds called jacanas, females are much larger than males. Males do all of the incubation of eggs and care for the young after they hatch. The females just lay the eggs and then leave; in some species of jacana, females will mate with a second or even a third male in one season. Females also fight each other over access to males. Males spend more time and energy in producing offspring. This means that the pressure for sexual selection is on females because they must increase the alleles for size and other beneficial features. I can keep practicing questions like this and how to expand my answer to hit more criteria and get a more thorough answer. Even though eggs are larger than sperm, the investment that males make in incubation and care of hatched young means that they expend more time and energy in parental care than females.

Related Questions

a) Why might selection have favored the preference female sage grouse have for the male sage grouse mating display? That is, what might males be signaling with this behavior, and why might it be in a femaleâs interest to choose a male based on his display?

b) What is the name of the mating system exhibited by great crested grebes, and what may have been one selective factor explaining why it evolved?

C) Propose a different hypothesis for why selection might have favored the preference female bowerbirds exhibit for blue coloration. (Isn't the reason why bowerbirds prefer the blue coloration is because it may be similar in color as to one of their resources attracting female bowerbirds to mate with them?)

- can someone also check if my answer to this question is correct (letter d).

d) Propose a hypothesis for why selection might have favored the preference females have for bower-building in male satin bowerbirds? That is, what might males be signaling with this behavior, and why might it be in a femaleâs interest to choose a male based on his display?

Bower building males signal females that their nest is the most suitable to lay their eggs and reproduce. It would be in the females best interest to choose a bowerbird with the best bower build because it is a preference that has been passed on in the species and by doing so its offspring will also choose intricate bower building mates.

lemoncheetah578

1)The use of deceptive signals is common in nature. Certainorchids, for example, lure pollinator wasps with flower petals thatsmell like receptive female wasps. This example can be viewed as aDarwinian puzzle because:

a. The proportion of orchid flowers that set fruit as a resultof successful pollination is actually pretty small.

b. Discriminating male wasps should be favoured by naturalselection so that they do not waste time, energy, and even sperm onorchid flowers.

c. Time and energy spent on orchids reduces the capacity of thewasp population to grow, since the deceptive plants slow theability of male wasps to fertilize all the eggs of theirfemales.

d. It is next to impossible to figure out how orchid flowersevolved to smell like the females of certain wasps.

2) During courtship, the males of some spider species offertheir mates a nuptial gift, a prey item, usually an insect of somekind, such as a cricket. Mating success for the male is highlydependent on the female accepting the gift. Researchers also notedthat males used white silk to wrap the generally dark-colouredgifts just as mated females do with their eggs sacs and wondered ifmales did this intentionally. (4 marks)

i. The last sentence in the paragraph above constitutes:

a. A causal question.

b. A hypothesis.

c. A prediction.

d. Test evidence.

ii. What theory was used to explore the courtship behaviourdescribed above?

iii. Which of the following predictions might likely be correct,given the presumption that males might be making their nuptialgifts look like eggs sacs?

a. The time it takes for a female to accept a nuptial giftshould be less for prey covered in silk that has beenexperimentally coloured brown instead of white.

b. Natural silk-covered prey should be comparable in lightreflectance to silken egg sacs

. c. Females should readily grab and hold silken egg sacs thathad been taken from them but then offered back as if they were anuptial gift.

maroonpig282

For each scenario, indicate which evolutionary process is most likely to be dominant.

1.	Genetic drift.
2.	Outbreeding depression.
3.	Directional selection.
4.	Stabilizing selection.
5.	Balancing selection.
6.	Disruptive selection
	SCENARIOS

A) A population of rabbits is primarily preyed upon by coyotes. Only the fastest rabbits escape once seen.

B) In a population of cone snails, the individuals of the most common color suffer the heaviest predation.

C) In widowbirds, males with longer tails attract more mates, but also suffer higher predation.

D) Fledging success is highest among bluebirds with four or five eggs per clutch, although bluebirds lay two to seven eggs per nesting attempt.

F) Among a certain species of fish, both large males that defend high quality nest sites, and smaller males that resemble female fish fertilize many eggs.

G) A Puerto Rican parrot population was decimated by a recent hurricane. It appears that most birds within the path of the storm were killed.

H) In a population of sparrows, scientists noted that the sparrows killed in a particular storm were birds with much longer or shorter than average wings.

I) Fossil evidence indicates that the small, forest dwelling ancestor of modern horses gave rise to much taller (more recent) ancestors as the environment changed to grassland.

J) A population of solid gray ground snakes is well camouflaged on the rocky beaches of the island it occupies. Snakes born to island snakes that mate with the banded snakes from the mainland that occasionally arrive on the island are more likely to be eaten by birds.

K) In ground finches, both small beaked and large beaked birds have higher survivorship than those with intermediate beak sizes.

rosecat955

BIOL 180 Study Guide - Final Guide: Sampling Error, Species Richness

BIOL 180 Full Course Notes

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