Classification Flashcards
Main principle in classification?
Groups must be monophyletic.
Why are vernacular names preferred?
Based on the language of everyday life, so don’t need to memorise or pronounce the Latinised scientific name.
Can refer to the appearance of the organism, making it easier to remember.
Problems with vernacular names?
Common names often have a very local distribution, so one organism in an area may have several names.
Common names can change with time.
A single common name may refer to more than one species.
Advantages with scientific names?
Names are associated with groups, so allows for relationships to be drawn between species.
Clarity - each species will only have one scientific name.
Universal - scientific names are standardised and accepted universally.
Interspecific relationship - help understand the similarities and differences between species of the same genera.
Define taxonomy?
Science of naming, describing and grouping living organisms.
Define phylogenetics?
Study of evolutionary relationships between/within groups of organisms.
Define systematics?
Inference of phylogenetic relationships between species.
Define dichotomous?
Divides into 2 branches.
Define monophyletic?
All share a common ancestor and contains all the descendants from a certain ancestor.
What were early attempts at classification based on?
Intuition (Theophrastus 371BC) or morphology (Dioscorides 1st century)
What did Gesner do?
Used more than one characteristic to classify. 16th century.
What did John Locke do?
Talked about how it was possible to guess the primary essence by observing as much of the secondary essence as possible. 17th century.
What were John Ray’s contributions?
Species definition: a group of individuals who share a unique combination of characteristics that can be replicated.
To preserve a species you need to grow plants from seeds to maintain sexual reproduction.
To classify you need to use as many characteristics as possible and allow for losses.
Don’t allow for one characteristic to become the priority.
His defined monocots have been shown to be monophyletic.
Linnaeus’ contributions?
18th century.
“Without permanent names there can be no permanence of knowledge”
Used binomial names for each species.
However, chose reproduction as the priority which was a step backwards.
Bentham and Hooker’s contributions?
19th century. Rejected Linnaeus and brought back Ray.
Used a hierarchical system. Defined the KPCOFGS system.