A4 unity and diversity of ecosystems Flashcards
biological evolution
change in the heritable characteristics (rooted in DNA) of a **population
what does it mean fro a theory to be falsified
it is shown that it is not true through the use of empirical evidence
three different molecular evidences for evolution
- DNA
- RNA
- Proteins
hox genes
the genes that play a role in determining your bodily developpement. These geners are incredibly similar across different types of organisms and would be hard to explain without a common ascestor and evolution
phylogenetic tree
a visual diagram that shows which species are most similar and related by comparing the similarity of a single gene
selective breeding
choosing organisms to mate together based on whether they have desirable characteristics
artificial selection
the result of selective breeding where organisms noe have combinations of traits that were not previously seen and have been curated by humans
homologous
structures
structures that share a similar internat structure despite being use for idfferent purposes (divergent evolution)
pentadactyl limbs
an example of homologous structres that is front or hind legs/arms that do or did have 5 digits
analogous structures
body parts that cary out the same function in different organisms but are structured differently internally (convergent evolution)
convergent evolution
when two species evolve independently but develop similar features and adaptations that suit their environment and become mroe similar
speciation
the formation of a new species by the splitting of an existing species (can no longer interbreed)
reproductive isolation
when populations can no longer interbreed with one another preventing gene flow (can be geographic, behavioral or temporal)
geographic isolation
there is a natural or man made barrier seperating males and females preventing mating
sympatric speciation
speciation that occurs when mating does not occur despite contact (casued by temporal or behavioral isolation)
allopatric speciation
physical geographic barrier leads to a lack of contact and the development of distincts species