speciation lesson

1. LIFE SCIENCES GRADE 12
The concept and two types of speciation
Allopatric and sympatric
Presented by Maseko Remember

2. THE SPECIES CONCEPT-DEFINITION
• A species refers to a group of organisms having similar characteristics in the same
population and are able to interbreed to produce fertile or viable offspring.
• Organisms that can mate but not produce fertile offspring are not regarded as the
same species.

3. SPECIATION
• The concept speciation refers to a process whereby new species are introduced
• It can be explained as being the formation of new species that of which can not
successfully interbreed. Should these species be able to interbreed or mate, they will
not be able to produce a fertile offspring.
• For example, should a donkey and a horse( two different species) mate, they will
produce a mule offspring, of which is infertile.

4. A MULE, FORMED WHEN A
DONKEY AND HORSE
INTERBREED

5. TWO TYPES OF SPECIATION
• There are two types of speciation as follows:
ALLOPATRIC SPECIATION- also referred to as geographic speciation, is a mode of
speciation that occurs when biological populations of the same species become
isolated from each other to an extent that prevents or interferes with genetic
interchange.
Various geographic changes can arise such as the movement of continents, and the
formation of mountains, islands, bodies of water, or glaciers. Human activity such as
agriculture or developments can also change the distribution of species populations.
These factors can substantially alter a region's geography, resulting in the separation
of a species population into isolated subpopulations.

7. SYMPATRIC SPECIATION- is the process through which new species evolve from a
single ancestral species while inhabiting the same geographic region. In evolutionary
biology and biogeography, sympatric and sympatry are terms referring to organisms
whose ranges overlap or are even identical, so that they occur together at least in
some places. If these organisms are closely related (e.g. sister species), such a
distribution may be the result of sympatric speciation

8. SYMPATRIC SPECIATION

9. REFERENCES
• https://www.slideshare.net/PaulVMcDowell
• https://www.slideshare.net/jessTrillo
• https://www.slideshare.net/Nihaad Mohammed
• https://www.slideshare.net/Mujahidhu Hussain
• https://www.slideshare.net/King Baloch