Ecosystem Essentials
An organism that manufactures its own food using sunlight via photosynthesis.
autotroph (or producer)?
A symbiotic relationship where both species involved benefit from the interaction.
mutualism
The primary evolutionary process proposed independently by Charles Darwin and Alfred Russel Wallace.
natural selection
Physical anatomical features, such as thick polar bear blubber or eagle talons, that aid survival.
structural adaptation
Preserved mineralized remains or traces of ancient organisms that document structural changes over geological deep time.
fossil record
Non-living physical and chemical components of an environment, such as sunlight, temperature, and precipitation.
abiotic factors?
Competition for limited resources occurring between members of DIFFERENT species.
interspecific competition
Random, unpredictable changes in DNA nucleotide sequences that serve as the ultimate source of completely new alleles.
mutations
An organism's observable physical characteristics, which selective pressures act upon directly.
phenotype
The primary selective pressure driving the shift from light to dark wing phenotypes in peppered moths during England's Industrial Revolution.
visual predation by birds (due to soot dark tree trunks)
The specific physical location or environment where an organism naturally lives and survives.
a habitat
A square frame of known area used by ecologists to randomly sample and estimate population density.
a quadrat
The four essential conditions needed for natural selection to occur, often remembered by the acronym V.I.S.T.
Variation, Inheritance, Selection, and Time
Human height and weight are examples of this variation pattern, showing a smooth continuum across a population.
continuous variation
The specialized cell division process in sexual reproduction that introduces genetic variation via crossing over and independent assortment.
meiosis
An ecological level consisting of ALL populations of DIFFERENT species living and interacting in a shared habitat.
a community
The dynamic delay observed in predator population peaks following shifts in prey availability.
predator-prey lag time (or predator-prey cycle)
In evolutionary biology, an individual organism's ability to survive and produce fertile offspring in its environment.
biological fitness
The practice of humans intentionally breeding organisms for specific desired traits, such as crop yield or dog breeds.
artificial selection (or selective breeding)?
The mechanism explaining why bacteria develop antibiotic resistance when non-resistant cells are killed off and pre-existing mutants survive.
natural selection
The complete functional role, position, and resource use of a species within its ecosystem.
an ecological niche
Ecological succession that occurs in an area where soil is already present following a disturbance, progressing much faster than primary succession.
secondary succession
The theory proposing that evolutionary change consists of long periods of stability interrupted by brief bursts of rapid change.
punctuated equilibrium
Internal biochemical or physiological processes, such as snake venom production or kidney water-retention mechanisms.
functional (or physiological) adaptation
An invasive species introduced to Australia in 1935 whose toxic glands drove selective pressures causing native snakes to evolve smaller heads.
the cane toad