Chapter 10: Life History Patterns Flashcards
1
Q
What is life history?
A
- the pattern of growth, development and reproduction
2
Q
What does life history include?(7)
A
- age at maturity
- method of reproduction
- mating system
- reproductive effort
- numbering of offspring
- amount of parental car
- timing of reproduction
3
Q
Explain trade-offs!
A
- limited resources that can be allocated
- organisms face trade-offs in life history characteristics
ex: costs and benefits in characteristics related to reproduction such as parental investment per offspring
4
Q
What factors affect fecundity?
A
- number of offspring often varies with size and age of parent. Many plants and ectothermic animals continue growing throughout adult life.
- production of young may reflect food supply because of effect on adult body size or through mortality of young
5
Q
Parental investment?
A
- theoretically, reproductive effort could go into many small young or a few large ones
6
Q
Parental investment in birds and mammals?
A
- few young, high parental care. Amount of care after birth depends on length of incubation
7
Q
Mating systems?
A
- the pattern of mating between males and females
8
Q
Types of mating systems?
A
- monogamy: formation of a lasting pair bond between one male and one female
- promiscuity: males and females mate with one or many of the opposite sex and form no pair bond.
- polygamy: the acquisition by an individual of two or more mates. It can involve one male and several females or one female and several males. A pair bond exists between the individual and each mate. The individual having multiple mates is generally not involved in the caring for the young.
9
Q
Mating systems:
- for many species males and females are sexually what?
A
- dimorphic : differ in body size, ornamentation and colour…sexual selection proposed to explain this
10
Q
What are the two sexual selections?
A
- Intrasexual selection
2. Intersexual selection
11
Q
Sexual Selection:
1. Intrasexual selection?
A
- male-male (or female-female) competition for opportunity to mate
- *leads to exaggerated secondary sexual characteristics (large size, aggressiveness, large antlers)
12
Q
Sexual Selection:
2. Intersexual selection ?
A
- differential attractiveness of one sex to the other.
13
Q
Mate choice based on resources?
A
- females may alternately select mate based on resources such as habitat or food that will improve fitness of female
ex: defended high quality habitat or territory
14
Q
- 11 Life History Characteristics:
- Suites of life history characteristics are associated with?
A
one another
15
Q
- 11 Life History Characteristics:
- MacArthur, Wilson, and Pianka proposed what?
A
r- and k- selection
