taxonomy & naming
what is the hierarchical classification system orders organisms from broadest to most specific
Domain → Kingdom → Phylum → Class → Order → Family → Genus → Species
in binomial names, this word is capitalised
genus
Term for traits that enhance survival or reproduction is known as:
what is the term for allele movement between populations
gene flow
which evolution produces similar traits in unrelated species due to similar environmental pressures?
convergent
In binomial names, this word is capitalised
genus
define evolution
a change in allele frequency within a population over time
define mutation
a random DNA change that introduces new genetic variation
how do homologous structures arise
common ancestry
define taxonomy
_______ is the scientific discipline of identifying, naming & classifying organisms based on shared characteristics, organising them into a structured hierarchy.
Name 5/5 of Darwins 5 major ideas
perpetual change
common descent
gradualism
natural selection
multiplication of species
define artificial selection
human-directed breeding for specific traits
human arms, bat wings and whale flippers are examples of this
homologous structures
what is systematics & provide an example
Systematics studies the diversity and evolutionary relationships among organisms
eg. shows how dogs, wolves & coyotes are related within Canidae
difference between micro & macro evolution
Macroevolution
- Origin & extinction of lineages
- Occurs gradually or in bursts
- Involves large-scale changes fixed in lineages
Microevolution
- Small-scale evolutionary change within a lineage
- Happens continuously
- Can accumulate to produce major changes over generations.
describe non-random mating
give an example in animals
when individuals in population do not mate by chance, but rather choose mates based on specfic traits/characteristics/appearance/behaviour/domiance.
- some individuals more likely to reproduce than others, which can influence the genetic structure of the population
- this includes sexual selection
- eg. birds choosing mates based on song complexity/dance
provide an example of how natural selection resulted in divergent evolution
Divergent evolution occurs when related species evolve different traits because they adapt to different environments or ecological niches.
Example: Darwin’s Finches
Finches on the Galápagos Islands descended from a common ancestor.
Different populations adapted to different food sources.
Natural selection favoured different beak shapes and sizes.
Examples:
Large strong beaks → crack seeds
Long narrow beaks → feed on insects
Pointed beaks → cactus feeding
Result:
One ancestral species evolved into many species with different traits.
what is cladistics & draw an example
groups species based on common ancestry, rather than just physical similarities.
describe what is speciation
Speciation :
Formation of new species
Usually via reproductive isolation
In animals, often due to geographical isolation (allopatric speciation)
natural selection: favourable heritable traits, that increases reproductive & survival success become more common over generations.
eg. darwins finches; birds with stronger beaks survive better when only hard seeds avail.
artificial selection: human directed breeding/selection for specific traits.
eg. livestock breeding; dairy cows selected for higher milk yield
sexual selection: form of natural selection hwere traits increase an indivduals success in attrating mates/competing for mates.
eg. peacock tail feathers; fems prefer males with larger, colourful tails
provide an example of how natural selection has resulted in convergent evolution
Convergent evolution occurs when unrelated species independently evolve similar traits because they live in similar environments and face similar selection pressures.
eg: Sharks and Dolphins
Sharks (fish) and dolphins (mammals) evolved similar streamlined bodies and fins.
They are not closely related, but both live in aquatic environments.
Natural selection favoured efficient swimming for hunting and movement in water.
similar body shape evolved independently in different lineages.
Another example you could mention:
Wings in birds and bats – both evolved flight independently.