Species And Taxonomy Flashcards
Modern definition of species
1- Similar in morphology ,behaviour ,biochemistry , and have the same ecological niche
2- Can breed together in their natural environment to produce fertile offspring but cannot breed successfully with other species
3- Share a common ancestor
Morphology is
The appearance of the species
Issues with the classification of a species using morphology, behaviour
-Species can have identical anatomy but different wing colours, are they different species?
-We can differentiate between organisms in identicle environments with similar morphology and by studying their biochemistry ( Their proteins, DNA )
How can you tell the difference between two species with similar morphology and ecological niches
By studying their biochemistry ( Their proteins, DNA
Issues with classification of a species using successfully breading
- Two species of plant could breed in an artificial lab
-Some closely related species can interbreed (Mules)
-It doesn’t take into account millions of asexually reproducing organisms
Issues with classifying a species using a common ancestor
Ancestry is difficult to determine and has only become possible using modern DNA analysis
What is speciation
When a new species arises when one existing species is reproductively isolated
How does speciation happen
Most commonly happens when the populations are physically separated geographically by natural selection
Speciation is gradual and can take thousands of years before the two populations are different enough to be considered desperate species
What’s it called when there are two different populations of the same species
Sub species which may in time become distinct species
Why do we classify using courtship behaviour
Because courtship behaviour (used for sexual reproduction) is innate (genetically programmed) so only members of the same species have that behaviour
What are the 5 things that courtship behaviours allow animals to do
1- recognise members of their own species
2- Attract mates of the opposite sex
3- identify a male capable of breeding
4- Synchronise the production of eggs and sperm
5- Form a bond and help raise offspring
Why is it important to recognise a member of the same species in courtship behaviour
When many similar species live in the same environment it’s important to breed correctly to produce fertile offspring
What are the three important innovations that Linnaeus brought to the modern classification system
1- a hierarchical structure
2- standard ranks and names on the hierarchy
3- a binomial nomenclature
A Hierarchical structure for classification rules
-There is no overlap between species
-a species can only appear once
What are the seven ranks to classification
King Phillip Came Over For Gold Sovereigns
Kingdom
Phylum
Class
Order
Family
Genus
Species
What is binomial nomenclature
Used to unambiguously name organisms by using both the genus and species
Why is the classification system called taxonomy
Because a taxon is a group of similar organisms at any level
What are the 5 kingdoms
Animalia
Plantae
Fungi
Protocista
Prokaryota
What is a domain
The newer classification placed above the kingdom.
-Domain Bacteria
-Domain Archea
-Domain Eukarya
What is phylogenetics / phylogenies
A family tree representing the evolutionary relationship rather than just convenient groups
What are the characteristics that scientists must use to determine phylogenies
-Morphology
-Ultrastructure (Microscopic features eg. Cell wall)
-Embryology (stages of embryo development)
-Paleontology
-Ethology (behaviour patterns)
-Biochemistry (metabolic pathways)
-Molecular biology (Sequence of DNA of proteins)
