Unit 7 NOT Quiz 2 NOT DONE ONLY SLIDE 16 Flashcards
What is a species?
A group of organisms that is capable of mating, exchanging genetic material, and producing viable, fertile offspring
Viable means the offspring can live to adulthood and mate. Fertile means that the offspring is capable of producing offspring.
What does viable mean in the context of a species?
The offspring can live to adulthood and mate
This is a key characteristic of a species’ ability to sustain its population.
What does fertile mean in the context of a species?
The offspring is capable of producing offspring at all
This is crucial for the continuation of a species.
Are mules considered a species? Why or why not?
No, because mules are non-fertile and cannot produce their own offspring
Mules are the offspring of donkeys and horses, illustrating the importance of fertility in species classification.
What is speciation?
Speciation is the formation of new and distinct species as a result of reproductive isolation.
Reproductive isolation prevents two organisms from interbreeding and producing fertile, viable offspring.
What does reproductive isolation mean?
Reproductive isolation means that two organisms can no longer interbreed and produce fertile, viable offspring.
This is a key mechanism in the process of speciation.
What are the two broad types of speciation?
- Sympatric Speciation
- Allopatric Speciation
These types describe different processes through which new species arise.
What does speciation look like drawn?
What is Allopatric speciation
What is sympatric speciation
Reproductive Barriers are a product of ___ in both ___ and ___ speciation
Evolutionary mechanisms
Allopatric
Sympatric
How does speciation affect diversity?
Increased species diversity allows for more genetic variation and therefore better survival against changes in the environment, including disease and natural disaster.
This prevents extinction of life on Earth.
What are reproductive barriers?
Term that refers to the various ways that organisms can become reproductively isolated.
What are the two types of reproductive barriers?
- Prezygotic barriers
- Postzygotic barriers
What’s a prezygotic barrier
What’s a postzygotic barrier
What is habitat isolation
True or false: habitat isolation can be allopatric or sympatric
True
What’s temporal isolation
What’s behavioral isolation
What’s mechanical isolation
Whats genetic isoloation
What reduced hybrid viability
Whats reduced hybrid fertility and what’s it caused by?
Hybrid breakdown
What does the fossil record indicate about species?
Includes examples of species that appear suddenly, persist unchanged, and then disappear
This suggests a non-linear pattern of speciation.
Who coined the term punctuated equilibria?
Niles Eldredge and Stephen Jay Gould
This term describes periods of stasis interrupted by sudden changes in species.
Define punctuated equilibria.
Periods of apparent stasis punctuated by sudden change
This concept contrasts with gradualism in evolutionary biology.
What is gradualism?
Change that occurs slowly over millennia or millions of years
Gradualism implies a more continuous and incremental process of evolution.
What is adaptive radiation?
A process where a population diversifies rapidly into many new, related species when entering a new habitat with little competition.
What conditions typically lead to adaptive radiation?
A new environment with little competition from other species and a wide variety of ecological opportunities.
True or False: Adaptive radiation only occurs in environments with high competition.
False.
Fill in the blank: Adaptive radiation can occur when a population enters a new habitat with little _______.
competition from other species.
What is adaptive radiation?
Adaptive radiation is the process by which organisms diversify rapidly into a wide variety of forms to adapt to new niches.
What makes adaptive radiation more likely to occur?
Adaptive radiation is more likely to occur when new niches become available.
Define ‘niche’ in ecology.
A niche is a population’s ecological role; the sum total of its use of biotic and abiotic resources.
Fill in the blank: A niche is the sum total of a population’s use of _______ and _______ resources.
[biotic] and [abiotic]
True or False: A niche only includes biotic resources.
False
What is adaptive radiation?
A single species rapidly adapts to fill available niches in an environment.
