Concepts of Species and Modes of Speciation - Essay Example

The theory of speciation can basically be traced back to a type of understanding of basic evolutionary processes.  In this way, speciation is a way in which one can describe the way that different groups with innately different characteristics can arise from groups of a similar species that share a common split ancestry (Singh 2010).  Such a theory can help to explain how animals such as ducks and other livestock first became domesticated and presented a clear shift from the common ancestry of the non-domesticated duck that has resultantly helped the domesticated duck to evolve to what can be noted today; a nearly flightless animal that carries a great deal more weight than its naturally occurring relative. 

In much the same way, environmental agents of selective pressures mean that key environmental factors can influence the way that creatures adapt to the environment or particular way of life that is most suited to the furtherance of their species within the given construct in question.  This of course denotes the Darwinian theories of natural selection and can be evidenced by the way that certain species of fish have adapted to their respective environments as a way to better provide themselves and their offspring with the chance of increased survival. 

Conversely, an environmental agent of selective pressures denotes the ways in which certain environmental factors act upon creatures to adapt them to the particular way of life that is necessitated within their environment.  Evidence of this can of course is seen in the giraffes of the savannah as they were increasingly necessitated to have longer and longer necks as a function of reaching the flora at the top of the tree canopy.  In this way, environmental agents of selective pressures can alternatively be read as a type of natural selection.

Lastly, with regards to the dispersion theory, this can ultimately be understood as a way in which different groups of the same species develop in different ways as a result of the geographic distance that separates them.  Evidence of this can of course is noted within the way that species in far-flung areas of Siberia and elsewhere mirror very little their cousins within distant regions.