1. Species Concept and Speciation Process

2. Recognizable ‘Kinds’ of Organisms

3. Species?

4. Taxonomy: dealing with variation
The scientist Linnaeus ( ) sought to classify organisms in an organized way to more easily study and keep track of them.
He also practiced medicine and specialized in syphilis
Binomial nomenclature
Genus species

5. Who cares about this? Taxonomists Conservation biologists
CITES, wildlife regulatory agencies
Politicians and developers?
Epizootiologists and Epidemiologists
Journal Clubs?

6. Species?

7. Head and Body Lice
Are the two separate species? The scientific name of the lice can be found either way in the in the literature:
Pediculus humanus humanus
Pediculus humanus capitus Or
Pediculus humanus
Pediculus capitus
The two taxa of lice are virtually indistinguishable morphologically except that the body louse is slightly larger than the head louse.
Body lice seem to be more important in the transmission of diseases (such as epidemic typhus) than head lice

8. Concept of Species What is a Species?
How does this concept fit into bioscience?
Systematics, ecology and evolution
Does the concept of species represent a testable hypothesis?
Is a single concept universal (apply to all life forms)?
Are there many concepts?

9. The Biological Species Concept
AKA the isolation concept
Championed by Ernst Mayr
Widely accepted by zoologists and botanists
Basically states that:
lack of gene flow leads to divergence between populations
reproductive isolation is test of separate species status i.e. different species can not interbreed

10. Problems with the biological species concept
Can’t be applied to many organisms
Asexual organisms
Bacteria
Links concept to a limited number of speciation processes
Overemphasis on gene flow
Some distinct populations can, but do not interbreed because of factors such as behavior or distribution
Some sympatric individuals can’t interbreed but natural selection maintains continuity in population

11. Reproductive isolation?
Wolbachia spp. is a bacterium that affects the reproduction of mosquitoes
Infected mosquitos limited to breeding with other infected mosquitos

12. Reproductive Isolation

13. Fossil Species

14. Change in populations

15. Speciation
Speciation results after heritable changes occur to such an extent that populations of organisms form separate, significantly different(?) clades. (cladogenesis)
Mechanisms
Genetic drift, hybridyzation,various incompatibilities genetic& behavioral etc..
Natural Selection
Modes of speciation
Allopatric
Peripatric
Sympatric

16. Fig

17. Evolution of Populations
Spectrum of characteristics in population
Population after selection
Different selection processes
Original population

18. Divergence in Population

19. Some other species concepts
Taxonomic species concepts
Morphospecies
Genospecies
Phylogenetic species
Recognition Concept
Cohesion Concept

20. Using DNA to classify species

21. Bioinformatics is a new field involving the use of technology to evaluate biological data
BioNumerics-Applied Maths