Topic 1 - Describing Biodiversities Flashcards
What are biotic factors?
Living factors which affect an ecosystem
What is species richness?
Measurement of the number of different species in an ecosystem
What is relative species abundance?
Measurement of how common a species is relative to its area
What are quadrats
Square grids used for sampling species in specific areas
What is percentage cover?
How much space a species occupies in a specific sample
What is Simpson’s diversity Index?
A measurement of diversity that accounts for species richness and evenness
What does a high SDI suggest about an ecosystem?
More complex food webs, more successful species, changes in an environment will be less damaging to the ecosystem
What is population density?
How many individuals per unit of area
What does population distribution mean?
The spatial distribution of individuals in a population
Population size
Number of individuals in a population
What are 4 biotic factors that affect size, density, and distribution of a population?
Predation, competition, disease, symbiosis
What are 3 abiotic factors that affect size, distribution, and density of a population?
Climate, substrate, land size
What system do we use to denote a species of organism?
Binomial nomenclature (genus, species)
What is the Linnaean system of classification?
Levels of classification based on morphological features
What are the 8 levels of classification in the Linnaean system?
Domain Kingdom Phylum Class Order Family Genus Species
Define Clade
A group of organisms that consists of a common ancestor and all its lineal descendants
3 Common assumptions of cladistics
- Any group of organisms are related by descent from a common ancestor
- There is a bifurcating pattern of cladogenesis
- Displays physical features
Asexual Reproduction
Production of offspring from 1 parent that are identical
Sexual Reproduction
Production of offspring (often from 2 parents) that are genetically unique from the parent through the fusion of gametes
What are the advantages of asexual reproduction?
- Fast
- Low energy mean of producing a large number of offspring
What are the advantages of sexual reproduction?
- Unique offspring with genetic variation which could lead to a potentially higher chance of survival in changing environment
K-selection Strategy
- Low number of offspring
- Higher energy
- Longer life span
r-selection Strategy
- High number of offspring
- Low energy and maintenance
- Shorter life span
Stratification
The vertical layering of habitats according to where plants/organisms grow
