10 Evolution and classification Flashcards
what is the definition of classification?
the grouping of organisms based on the similarity of features
what is taxonomy?
the science of studying classification and the differences between species
what is phylogeny?
the study of evolutionary relationships between organisms
what is a species?
a group of organisms which can interbreed successfully to produce fertile offspring
what common traits do species share?
genetics
biochemical features
physiological features
anatomical features
ecological niche
what is the biological species concept (BSC)?
a group of organisms with similar morphological, physiological, biochemical and ecological features that can interbreed to produce fertile offspring
what is a criticism of the BSC?
it does not consider species that reproduce asexually
what is the phylogenetic species concept (PSC)?
a group of organisms that share a common ancestor and have the same evolutionary history
what are two advantages of the PSC?
a continuous tree ∴ doesn’t have to definitively classify
avoids misleading hierachy
what are the 8 taxons (from largest to smallest)?
Domain
Kingdom Phylum Class Order Family Genus Species
how does the binomial naming system use the taxons?
{Genus species} - e.g. Homo sapiens
can be abbreviated to H. sapiens
must be italicised or underlined when written
what are the three domains?
Eubacteria
Archaebacteria
Eukaryota
how is DNA used for classification?
genomes of 100+ species known
DNA codes for a specific sequence of amino acids ∴ more similarity in DNA –> closer relationship
which proteins are primarily used in classification?
haemoglobin
cytochrome C
how are anatomical features used for classification?
similar organisms grouped
- members of same species can look v. different
- does not account for convergent evolution
how are fossils used for classification?
DNA can be retrieved from recent fossils for molecular analysis
evolutionary relationship estimated using morphological features
how can immunological evidence be used for classification?
proteins from one species act as an antigen if injected from another species, provoking an immune response
similar species have similar antigens ∴ similar immune response ∴ similar antibody production
how can embryological evidence be used for classification?
early embryos can look very similar
what are the features of the optimum section of DNA for DNA barcoding?
universal to most taxa
short
universal variation between species
little variation within species
why is mitochondrial DNA often used in DNA barcoding?
has a faster rate of mutation than chromosomal DNA
∴ produces significant difference in genetic sequence