Evolution principles and life histories Flashcards
What are the 2 levels of analysis in veterinary science?
Proximate causation - mechanistic approach
Ultimate causation - whole animal approach
Domestic animals are products of design by what process?
Natural selection
What is variation?
Individuals in a species differ in their characteristics
What is the definition of hereditary?
Parents pass on their distinctive characteristics to their offspring
What is the definition of differential reproduction?
Because of their inherited characteristics, some individuals leave more offspring than others
How do biologists classify species?
Based on their evolutionary relationships
What are the consequences of natural selection?
Species diversity
What is the hierarchy order?
Kingdom Phylum Class Order Family Genus Species
What are life history traits?
Traits related to growth, reproduction and longevity
Traits that interact to determine individual lifetime reproductive success
Give some examples of life history traits
- Size at birth
- Growth pattern
- Age at maturity
- Size at maturity
- Number, size and sex ratio of offspring
- Age and size specific reproductive events
- Age and size specific mortality schedules
- Longevity
Species with ‘fast’ life histories typically produce…?
More offspring
Are altricial animals fast or slow life history traits?
Fast
Give some features of slow life history traits
Precocial Reproduce late Small litter Large neonates Long gestation High parental care Long lifespan
Fitness (W) is calculated by multiplying what 3 factors?
Number of offspring
Quality of offspring
Adult lifespan
What benefits come with a high extrinsic mortality risk (trade off)?
Early maturation
Higher probability of surviving to reproduce
Higher potential reproductive success by starting early
What are the benefits of late maturity that come with a low extrinsic mortality risk?
Can grow larger and have a higher fecundity
Can invest more offspring
What decisions are faced by an animal when it comes to reproducing?
When to reproduce? - need to invest energy in growth
How to allocate resources available for reproduction - large number of smaller offspring or vice versa
What factors are often reduced in large litters?
Offspring growth rates
Weaning size
What does lifespan increase with in mammals and birds?
Body size
Which species tend to have a faster rate of ageing?
Those that are at a higher risk of of dying by extrinsic causes such as predation and disease
Why do large breeds of dog have shorter lifespans?
Faster growth rates in early life