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Advanced Higher
Unit 2 - Sex and Behaviour
Question | Answer |
---|---|
Do females or males show the greater parental investment? | Females |
Explain why females have a greater energy expenditure | Eggs are costly to produce; greater parental care in terms of nest building etc |
State the two types of parental investment | R-selected and K-selected |
State the problem of sex for sessile organisms | Sessile organisms are unable to move |
State the solutions of sex for sessile organisms | Being self-fertile; synchronised spawning; use of other organisms to carry gametes |
When parental investment is costly this increases the chance of | Production and survival of young |
Define a K-selected species | Species has a decreased quantity of offspring with a corresponding increase in parental investment |
Define a R-selected species | Species has an increased quantity of offspring with a corresponding decrease in parental investment |
Compare the size of offspring in K-selected and R-selected species | K-selected have large offspring and R-selected have small offspring |
Compare the quantity of offspring in K-selected and R-selected species | K-selected have a low quantity of offspring while while R-selected have a high quantity of offspring |
Which type of parental investment prefers quantity over quality in offspring | R-selected |
Which type of parental investment prefers quality over quantity in offspring | K-selected |
What is the definition of polygamy | Mating with more than one partner in a reproductive season |
What is the definition of monogamy | Mating with only one partner |
What is the advantage of internal fertilisation | Allows female choice; less gametes are required as chance of success is high |
What is the disadvantage of internal fertilisation | Risk of parasitic disease |
What is the advantage of external fertilisation | No increased risk of parasitic infection |
What is the disadvantage of external fertilisation | More gametes are required as chance of success is low; no female choice |
State the term used to indicate the different body forms of males and females belonging to this species. | Sexual dimorphism |
State the term for species in which the female is larger or more brightly coloured | Reversed sexual dimorphism |
Why is it important for females in many species to be inconspicuous | Harder for predators to see them OR survival chances of their young increases |
Is sexual selection a random or non-random process | Non-random |
State how females assess male fitness | Honest signals |
Honest signals can indicate | Good genes and low parasite burden |
Give three examples of honest signals | Roaring; dancing; squandering resources |
Why do females get to choose during sexual selection | As they invest a lot more energy in egg production than males do in sperm production |
Give examples of ways males are conspicuous | colourful; large in size; behaviours such as dancing |
Why do males have to display elaborate courtship behaviours | non random evolution that increases reproductive success through female choice |
Which male features would increase their access to females through male-male rivalry | Large size; weaponry |
Explain what is meant by a lekking species | Males gather and compete in communal area (lek) and this allows females choice to occur |
In lekking species, alternative successful strategies of dominant and satellite males. State the strategies for dominant and satellite males | Dominant: male-male rivalry Satellite: sneakers |
Define a sneaker male | Sneakers can become inconspicuous by resembling a female in order to avoid male-male rivalry |
What is a sign-stimulus | A feature from an animals environment that causes a particular response |
What is a fixed action pattern (FAP) response | An instinctive behavioural response triggered by a sign stimulus |
What is imprinting | Irreversible developmental processes that occur during a critical time period in young birds may influence mate choice later in life. |
State one function of male displays | To attract females/let female select the 'best' male |
Male birds use singing to court females, why is this regarded as sexual selection? | It is subject to female choice, increasing chance of mating with female |