Evolution, Biodiversity, and Population Ecology Flashcards
Species
a population or group of populations whose members share characteristics and can breed with one another and produce fertile offspring
Population
a group of individuals of a species that live in the same area
Evolution
a process where populations change over multiple generations as genetic changes alter their physical and behavioral characteristics
Natural Selection
a process in which traits that enhance survival and reproduction are passed on more frequently to future generations than those that do not
Adaptation
the process where, over time, characteristics (traits) that lead to better reproductive success become more prevalent in the population
Adaptive trait
a trait that promotes reproductive success (venom, mimicry, behavioral)
Mutations
accidental changes in DNA that may be passed on to the next generations
What is divergent evolution?
related species in different environments experience different pressures and evolve different traits
What is convergent evolution?
unrelated species may acquire similar traits because they live in similar environments
Artificial selection
changes under human direction. domesticated dogs, cats, and livestock
Biodiversity
the variety of life across all levels of biological organization
Speciation
the process of generating new species from a single species
Allopatric Speciation
populations become physically separated through separation by plate tectonics, human development, natural disasters damaging habitat (volcanos, earthquakes), moving species, etc
Phylogenetic trees
diagrams that show relations among species, groups, genes, etc. by looking at characteristics and DNA. Show how species evolve over time
Endemic species
a species that only exist in a certain specialized area (very vulnerable to extinction) (ex: Formosan Rock Macaque, Javanese Rhinos, Paphiodetilum fowliei)
Background extinction rate
constant, slow rate of extinction
Ecology
the scientific study of:
- distribution and abundance of organism
- the interactions among organisms
- the relationships between organisms and their environments
Population ecologists
looks at the dynamics of population change. Where are they? why is it there? how many are there? why are there that many? (distribution and abundance and whats causing that population to change)
Niche
an organism’s role in its community includes resource use and interactions with another organism (job)
Habitat
the environment where an organism lives
- it includes living and nonliving elements
Specialists
species that have narrow niches and specific needs
Generalists
species with broad niches
Population density
number of individuals per unit area
Population distribution
spatial arrangement of organisms within an area
(random, uniform, clumped)