Podcast
Questions and Answers
What is the process by which a new species emerges?
What is the process by which a new species emerges?
- Mutation
- Natural selection
- Adaptation
- Speciation (correct)
What is the difference between microevolution and macroevolution?
What is the difference between microevolution and macroevolution?
Microevolution deals with changes in the gene pool of a single population. Macroevolution considers the broad pattern of evolutionary change over long periods of time and includes the origin of new groups.
What is taxonomy?
What is taxonomy?
The branch of biology that names and classifies species and groups them into broader categories.
What is the biological species concept?
What is the biological species concept?
What is reproductive isolation?
What is reproductive isolation?
What is the morphological species concept?
What is the morphological species concept?
What does the ecological species concept focus on?
What does the ecological species concept focus on?
What is the phylogenetic species concept?
What is the phylogenetic species concept?
Which species concept is most useful for identifying species in the field?
Which species concept is most useful for identifying species in the field?
What is a reproductive barrier?
What is a reproductive barrier?
What are prezygotic barriers?
What are prezygotic barriers?
Temporal isolation is a type of _____ barrier; occurs when species breed at different _____?
Temporal isolation is a type of _____ barrier; occurs when species breed at different _____?
What is habitat isolation?
What is habitat isolation?
What is behavioral isolation?
What is behavioral isolation?
What is mechanical isolation?
What is mechanical isolation?
What is gametic isolation?
What is gametic isolation?
What is a postzygotic barrier?
What is a postzygotic barrier?
What is reduced hybrid viability?
What is reduced hybrid viability?
What is reduced hybrid fertility?
What is reduced hybrid fertility?
What is hybrid breakdown?
What is hybrid breakdown?
Two closely related cichlids live in Lake Victoria, but one feeds on detritus along the shoreline and the other is a bottom feeder in deep water. This is an example of _____ isolation, which is a _____ reproductive barrier.
Two closely related cichlids live in Lake Victoria, but one feeds on detritus along the shoreline and the other is a bottom feeder in deep water. This is an example of _____ isolation, which is a _____ reproductive barrier.
What is allopatric speciation?
What is allopatric speciation?
A new species will not arise just because a population becomes geographically isolated. For _____ speciation to occur, changes in the gene pool must produce _____.
A new species will not arise just because a population becomes geographically isolated. For _____ speciation to occur, changes in the gene pool must produce _____.
What is sympatric speciation?
What is sympatric speciation?
What is a polyploid?
What is a polyploid?
What barrier isolates a viable, fertile, polyploid plant from its parental species?
What barrier isolates a viable, fertile, polyploid plant from its parental species?
____% of living plant species are descendants of ancestors that formed by polyploid speciation.
____% of living plant species are descendants of ancestors that formed by polyploid speciation.
Why are errors in mitosis or in meiosis a necessary part of speciation by hybridization between two species?
Why are errors in mitosis or in meiosis a necessary part of speciation by hybridization between two species?
How do females of the Galapagos finch Geospiza difficilis respond to sounds of males from the same island?
How do females of the Galapagos finch Geospiza difficilis respond to sounds of males from the same island?
What is a hybrid zone?
What is a hybrid zone?
Why might hybrid zones be called 'natural laboratories' in which to study speciation?
Why might hybrid zones be called 'natural laboratories' in which to study speciation?
What is adaptive radiation?
What is adaptive radiation?
What three types of opportunities might set the stage for adaptive radiation?
What three types of opportunities might set the stage for adaptive radiation?
What are punctuated equilibria?
What are punctuated equilibria?
How does the punctuated equilibrium model account for the relative rarity of transitional fossils?
How does the punctuated equilibrium model account for the relative rarity of transitional fossils?
Flashcards are hidden until you start studying
Study Notes
Speciation
- Emergence of a new species, linking microevolution to macroevolution.
Microevolution vs Macroevolution
- Microevolution involves changes in a single population's gene pool.
- Macroevolution encompasses broader evolutionary changes over time, including new group origins.
Taxonomy
- Branch of biology dedicated to naming and classifying species, organizing them into broader categories.
Biological Species Concept
- Defines species as populations that can interbreed in nature and produce fertile offspring, described by Ernst Mayr in 1942.
Reproductive Isolation
- Mechanism that prevents genetic exchange, maintaining separation between species.
Morphological Species Concept
- Classifies species based on physical traits like shape and size; applicable to both asexual organisms and fossils, yet can be subjective.
Ecological Species Concept
- Defines species by ecological niches and unique adaptations within a biological community.
Phylogenetic Species Concept
- Identifies species as the smallest group sharing a common ancestor, often analyzed through DNA and morphology.
Identifying Species in the Field
- Morphological species concept is most practical as it relies solely on appearance without needing additional contextual information.
Reproductive Barriers
- Biological features preventing interbreeding with closely related species; categorized as prezygotic or postzygotic barriers.
Prezygotic Barriers
- Five types prevent mating or fertilization:
- Temporal Isolation: Species breed at different times.
- Habitat Isolation: Species occupy different habitats within the same area.
- Behavioral Isolation: Differences in mating behaviors reduce attraction.
- Mechanical Isolation: Incompatibility of reproductive structures.
- Gametic Isolation: Sperm and egg from different species fail to unite.
Postzygotic Barriers
- Function after hybrid zygotes form, including:
- Reduced Hybrid Viability: Hybrids do not survive well or reach maturity.
- Reduced Hybrid Fertility: Hybrids are fertile but produce non-viable gametes.
- Hybrid Breakdown: Initial hybrids are fertile but their offspring are weak or sterile.
Allopatric Speciation
- Arises from geographic barriers to gene flow, necessitating reproductive isolation for new species to form.
Sympatric Speciation
- New species develop in the same geographic area as the parent species.
Polyploid
- Refers to organisms with more than two sets of chromosomes; common in plant speciation through cell division errors.
Polyploid Speciation in Plants
- Approximately 80% of living plant species share ancestry linked to polyploidy.
Role of Chromosomal Errors
- Errors in mitosis or meiosis create hybrid organisms capable of forming viable gametes by duplicating chromosome sets.
Behavioral Isolation in Finch Populations
- Finch females respond selectively to males from their island, indicating developing behavioral barriers in geographically isolated groups.
Hybrid Zones
- Areas where different species interbreed, producing hybrid offspring; serve as valuable sites for studying speciation.
Adaptive Radiation
- The rapid evolution of various species from a common ancestor, often triggered by ecological opportunities.
Factors for Adaptive Radiation
- New habitat colonization, post-extinction niches, and the emergence of novel morphological traits can drive adaptive radiation.
Punctuated Equilibria
- A model describing long periods of stability in species, punctuated by rapid speciation events, proposed by Niles Eldredge and Stephen Jay Gould.
Transitional Fossils and Speciation
- Relative scarcity of transitional fossils arises when speciation occurs quickly compared to a species' existence, making such transitions hard to find in the fossil record.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
