Species Concepts (5) Flashcards
(104 cards)
Species (in general)?
= organisms that can reproduce naturally with each other & produce fertile offspring.
How do we distinguish species?/ What criteria should we use to distinguish species? (4)
• Morphology.
• Habitat (ecological niche).
• Ability to interbreed.
• Common ancestry/Relatedness (Genetics).
List the Species Concepts (SC)? (7)
• Morphological SC.
• Phenetic SC.
• Biological SC.
• Recognition SC.
• Ecological SC.
• Evolutionary SC.
• Phylogenetic SC.
Morphological SC?
= species is a group of organisms with similar morphological & anatomical characteristics, but are different from other species.
Eg of Morphological SC?
Genus Panthera (“predator of all”) has 4 species (tiger, lion, leopard, cheetah) which differ in pattern, size & skull anatomy.
What does the “most recent” Phenetic SC include?
Quantitative measurements.
What enables you to place individuals in any 1 species?
Diagnostic characters (data types).
Explain the 2 data types?
● Categorical
= grouped.
● Continuous
= data that can take on any value.
Pros of Morphological SC? (3)
• Applies to sexual & asexual organisms (including bacteria).
• Applies to fossils for macroevolutionary studies.
• Enables comparison of fossils & current species.
Cons/Problems of MSC? (4)
• Variation within a species.
• Cryptic species.
• Lack of morphological differences between species.
• Sexual dimorphism.
Biological SC?
= species are members of populations that actually or potentially interbreed in nature.
Eg of BSC? Explain.
Western & Eastern Meadowlarks
- Look similar but don’t interbreed.
- Have different mating songs.
Kinds of reproductive isolating mechanisms? (2)
• Premating/Prezygotic mechanisms.
• Postmating/Postzygotic mechanisms.
List the Premating/Prezygotic mechanisms? (5)
• Ecological/Habitat isolation.
• Seasonal/Temporal isolation.
• Sexual/Behavioral isolation.
• Mechanical isolation.
• Gametic isolation.
Gametic isolation?
= where there is molecular incompatibility of the sperm & egg.
Premating/Prezygotic mechanisms = …?
Gamete related.
List the Postmating/Postzygotic mechanisms? (3)
• Hybrid inviability.
• Hybrid sterility.
• Hybrid breakdown.
Hybrid inviability?
= wherr zygotes are less viable.
Hybrid breakdown?
= where the F2 hybrids are less viable.
Egs of Hybrid sterility? (2)
• Liger (Lion+Tiger).
• Mule (Donkey+Horse).
Cons/Problems of BSC? (5)
• “Potentially interbreeding” suggests separate species & is difficult to determine.
• Asexually reproducing organisms.
• Ring species.
• Chronospecies.
• Hybrids.
Egs of Asexually reproducing organisms as a problem of Biological SC? (2)
• Aspergillus fungi.
• Bacteria.
Ecological SC?
= species is a set of organisms exploiting the same ecological niche.
What controls the division of resources in Ecological SC? (2)
• Ecological processes.
• Evolutionary processes.