Week 6- Evolution and Species Flashcards
To consider living organisms as members of different species, we must consider ____
The magnitude and types of differences individuals have
It is a working definition of a species and/or a methodology for determining whether or not two organisms are members of the same species.
Species concept
Types of species concept
-Typological/Morphological Species Concept
-Nominalist Species Concept
-Biological Species Concept
-Evolutionary Species Concept
This type of species concept do not exhibit any relationship with each other.
Typological/Morphological Species Concept
There is a finite number of varieties of living organisms that exist on earth in this concept.
Typological/Morphological Species Concept
Typological/Morphological Species Concept is depicted by _____ and _____ in their philosophies.
Aristotle and Plato
It is a concept that states that species cab be differentiated from other species by their physical features, which was formulated by Cain (1954, 1956)
Morphospecies concept or morphological species concept
It is a belief that nature only produces individuals.
Nominalistic Species Concept
These concepts do not have any scientific basis.
Nominalistic Species Concept
It believes that the species have been invented to be referred to big numbers of individuals jointly.
Nominalistic Species Concept
It defines species as a group of interbreeding natural population.
Biological Species Concept
Members of species exhibit the following attributes:
*Reproductive community (recognize one another as potential mates)
*Ecological Unit (all the members cooperatively form a unit)
*Genetical Unit (comprises a large, inter-communicating gene pool)
The flaws to the biological species concept had led the paleontologists to formulate this concept.
Evolutionary Species Concept
____ defined in 1961 that an evolutionat species is a lineage evolving seperately from others.
Simpson
___ stated that an evolutionary species are a single lineage of ancestral-descendant population
Wiley (1978)
Here, reproductive barriers prevent the two species from exchanging genes through reproduction.
Reproductive Isolation
It means two individuals are prevented from successful reproduction and kept genetically distinct from each other.
Reproductive Isolation
Two individuals are unable to mate as they live in geographically different areas.
Ecological Isolation
Mating is prevented because the reproductive organs are mature at different times.
Seasonal Isolation
Two species are so different that one female individual is able to recognize only the male of its species.
Ethological/Behavioral Isolation
The male and female organs for mating differ in different species and orevent their union.
Mechanical Isolation
The sperms of one species are not able to survive in the female tract of another species.
Physiological Isolation
If a zygote formed from different species is performed, it will die after some time or die in its development.
Zygotic and Developmental
A hybrid or a zygote formed from different species may lead to a normal life but cannot reproduce.
Hybrid Sterility
In rare cases, all above mechanisms fail and a hybrid is fertile. It can only produce one generation.
F2 Breakdown