Understanding Diversity Flashcards
What are the two types of diversity within species?
- phenotypic diversity (observed variation among individuals in morphology, development or behaviour)
- genotypes diversity (genes an organism inherits)
What are the four evolutionary forces that contribute to generating diversity?
- mutation
- migration
- genetic drift
- natural selection
What type of mutations can be passed on and which mutations only affect the individual in which they occur?
- only germline mutations can be passed on (in cells that produce eggs and sperm)
- somatic mutations only affect individual in which they occur e.g cancer
Are mutations advantageous?
No, they can be neutral or advantageous as well.
What is biological fitness?
Ability to reproduce offspring
What is migration (gene flow)?
Movement of genes between populations. Change in frequency of particular individuals. Evolutionary event
How does migration (gene flow) affect genetic variation of population?
Increases genetic variation by introducing or reintroducing genes to different parts of the population
The less gene flow between two populations, the ____ likely they will evolve into separate species.
More likely
What is genetic drift? Does it produce adaptations? What are the two outcomes it results in? What size population is it typically associated with?
Random changes to the genetic makeup of a population. It DOES not produce adaptations.
- leads to bottleneck effect (greatly reduced population) or founder effect (established with very few individuals)
- associated with small populations
What are the three requirements for natural selection?
- Individuals vary in some trait e.g colour
- The trait is heritable (has a genetic basis)
- Trait affects fitness (individuals with form of trait are more likely to reproduce)
Does selection act on species or individuals?
It acts on INDIVIDUALS not species
What is the abiotic environment?
Physical resources required to live, such as ambient temperature water abundance and water salinity
What is the biotic environment?
Other organisms that share the environment and can exert selection pressure.
What is Batesian mimicry?
Benign (doesn’t have toxins) Batesian mimic resembles noxious or dangerous model.
Predators avoid eating them
What is aggressive mimicry?
- method of obtaining food
- e.g frog fish have lure that mimic is worms
- spider has odour same as ants, allows it to gain access to ant nest and eat them
