Biodiversity Flashcards
Behaviour
How organisms respond to the biotic and abiotic environment
Coping mechanism
Morphology + Physiology + Behaviour
Fitness
Individual’s ability to reproduce successfully and passes on their genes to the next generation’s gene pool
Planetary health steps
- Primary observations
- Diagnose problems (Understanding the variable that is the problem and what surrounds it)
- Prescribe treatments for remediation and restoration
- Advocate for ecosystem health
The rates of ecosystem collapse
Pulse - Very fast, happens in a short time
press - ongoing change, global climate change indicators
Types of ecosystem collapse
- Abrupt
- Smooth
- Stepped
- Fluctuating
Ecological significance of behaviour
- Links individuals with their environment
- The interaction between biotic and abiotic environment
- Affects demographics (population level)
Evolutionary significance of behaviour
- Affects fitness
- Depending on the genes being passed on to the next generation
- The genes can either be advantageous or disadvantageous
- The survival and behaviour of the animals are also dependent on this
Theories on foraging
Optimal foraging theory
Marginal foraging theorem
What does the optimal foraging theory states
Predicts foragers should maximise net rate of food (=energy) intake and focuses on the efficiency of foraging. Assumed to be in a non-depleting environment. It is flawed as most foragers are also prey so foraging strategies should be more linked to predator avoidance strategies
Marginal foraging theorem
Foragers should leave the food patches when have eaten most or all of the food out. When capture/harvest rate at patch < average capture/harvest rate
Strategies to avoid becoming food
- Hiding
- Run away
- Group
- Act costly
- Be costly
- Feed in safe places/times
Logistic growth
Growth first starts as exponentially growing, growth then starts to slow down at higher numbers, then growth stops when it reaches the carrying capacity limit
Two types of growth rates
Instantaneous - Population that keeps breeding (no restriction in reproduction)
Discrete - Where population breeds at certain times (seasonal reproduction)
Demographic rates in a ‘closed’ system
Only takes account of birth and death rates where
Nt + Births - Deaths
Demographic rates in a ‘open’ system
Takes account of emigration and immigration of population
MRR (Mark Release Recapture)
a method that estimates total population size from a sample proportion. Assumed to be in a closed population, all individuals are marked and have not lost their mark
Metapopulation
Collection of all local populations interacting together where demographic rates vary spatially
Population Viability Analysis (PVA)
A tool to model population dynamics over time. Gives input environmental variables/variations to give a good prediction of the population
What info does PVA need?
- Fecundity (probability of birth)
- Population size/carrying capacity (K)
- Mortality
Chances that contribute to extinction
- Demographic stochasticity (random birth and deaths)
- Environmental stochasticity (environmental variation)
- Catastrophe
Biotic homogenisation
A process by which two or more spatially distributed ecological communities become increasingly similar over time
Spatial distribution
Difference in groups of organisms that are associated with the different vegetation across the landscape
Temporal distribution
Communities can change over time due to allowing local colonization or driving extinctions of other species depending on the change that happens over time
Grazing food chain
Primary food base is green plants or algae
Detritus food chain
Primary food base is dead organism
Genetic drift
Reduces genetic variation in a population
Species richness
Number of species in a community
Species diversity
The number of different species in a particular area and their relative abundance.
genetic diversity
the difference between animals of the same species
