species Flashcards
why are species important to biologists
knowing biodiversity
monitor change of natural enviornmental changes and changes because of human activity
what do biologists look for in species
adaptations within a species
changes in number of species in specific enviorment
what species concept did linneaus develop
morphological species concept
whats the morphological species concept
only looked at features and apperance of species to classify them
whats difficult about classifying species with morphology
apperance of organism can be effected by lots of things
huge variation within closely related group of organisms
how does sexual dimorphism effect morphology
male and female look different so could be said to be different species when same
reproductive or biological species concept
if two organisms can reproduce to make fertile offspring they are the same species
definition of species
group of organisms with similar features that interbreed to produce fertile offspring
advantages of reproductive or biological species concept
overcomes sexual dimorphism
disadvantages of reproductive or biological species concept
populations of organisms may not interbreed because of where they live not because they are different species
second definition of species
group of organisms in which genes can flow between individuals
molecular phylogeny
breaking down code to find similarities and differences between DNA of species
ecological species model
based on ecological niche occupied by organism
negatives of ecological species model
niche definitons very and many organisms have more then one niche
mate recognition species model
based on unique fertilisation methods including mating behaviour
weaknesses of mate recognition species model
many species interbreed with organisms and produce fertile offspring but are different species
genetic species model
based of DNA evidence
positives and negatives of genetic species model
-advanced tech- used more
- have to work out what percentage of difference makes it not or same species
evolutionary species model
based on shared evolutionary shared history between organisms
weaknesses of evolutionary species model
no clear evolutionary pathway for any organsim
limitations of species models
finding evidence of species mating- mating programms expensive
can hybrids be own species or same
many organisms dont repduce sexually
fossil organisms have DNA hard to extract
what happens in DNA sequencing
all or part of the organisms base sequences are worked out
what does DNA sequencing lead to
DNA profiling
whats DNA profiling
looks at non coding areas of DNA to identify patterns
how can patterns be used in DNA profiling
used to identify relationships between individuals and even between species
whats the need for bioinformatics
DNA profiling and sequencing makes so much data that it would be impossible for human to go through and search all patterns
why is identifying species from phenotype difficult
external conditions can result in major differences in appearance of individuals of same species
whats DNA profiling important for
market place ethics
understanding and treating infections
CBOL
consortium for the barcode of life
IBOL
international barcode of life project
ECBOL
european consortium for the barcode of life
what are the barcode companies
large organisations that are developing DNA barcodes for norm for identifying species
what does DNA barcoding include
looking at short genetic sequences from part of genome common to particular groups of organisms
how is DNA barcoding strong
good at identifying fish, bird and insects
how is DNA barcoding weak
cant be used for plants because evolve to slowly to see significant difference in genetics
how are plants barcoded
two gene regions in chloroplasts that can be used to split groups
what should happen to organism being barcoded
organism should be preserved
