Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
35 Cards in this Set
- Front
- Back
|
1. What is a species? 2. What is macro-evolution? 3. How does macro-evolution occur? 4. What century was Aristotle's time? |
1. A group of species that share a set of distinctive attributes in nature 2. Evolution at a large scale relating to the formation of a species/group of species 3. By the accumulation of microevolutionary changes 4. 4BCE |
|
|
1. Describe what people believed during Aristotle's time regarding how organisms came into being |
They believed that organisms arose from spontaneous generation- nonliving materials give rise to living organisms E.g. frogs/worms come from mud and mice come from rice |
|
|
1. How many species have been identified? 2. What is the old and new estimates of the range of unidentified species? 3. What are the 2 difficulties in identifying a species? 4. What is sometimes used? |
1. 1.4M 2. before: 10-100M; now:5-50M- mostly due to unidentified prokaryotes 3. *When members of a species separate into distinct populations and are undergoing the slow process of evolution *When populations accumulate genetic changes that make differences apparent but it is difficult to constitute them as different species. 4. Subspecies classification |
|
|
Describe what happens to a species when its members are separated for a a) a long time b) a short time |
a) Develop more differences- may constitute as different species b) More similar relative to each other- still from the same species. |
|
|
1. What are the 4 main species concepts 2, What is the extra concept that encompasses all of the main 4 concepts? |
1. *Phylogenetic *Biological *Evolutionary *Ecological 2. General-lineage concept |
|
|
Phylogenetic Species Concept -How is a species identified? -What was used historically -What is now used -Pro -Cons -E,g |
*Species is identified as a group of organisms that share a unique combination of characteristics *Physical traits were used historically to determine species, now DNA can be used :) Can be applied to all organisms :( Difficult to choose what characters to consider and the degree of dissimilarity :(Some members of the same species may look different while organisms of different species look the same *Dyeing frog and Northern/Southern Leopard frog |
|
|
Biological species concept -How is a species identified? - What prevents breeding with other species? -Who are the two scientists that formed the concept and which aspect did they propose? -Problems |
*A species is identified as a group of organisms that are capable of interbreeding with each other to produce viable, fertile offspring, and not capable to interbreed with different species *Reproductive isolation prevents the breeding of 2 different species *1920s- Theosidius= reproductive isolation *1942- Ernst Mayr= interbreeding between members of the same species produces viable/fertile offspring :(Difficult to determine if two populations are reproductively isolated :( 2 species may be capable of interbreeding but don't :(Doesn't apply to asexual species or extinct organisms |
|
|
Evolutionary Species concept -How is a species identified? - Con - What's a lineage? |
*A species is derived from a single lineage that's distinct from other lineages in which it has its own evolutionary tendencies and historical fates. :(Difficult to identify unique species b/c it's hard to examine/quantitate lineages= it's incomplete *The genetic relationship between individuals and their ancestors. |
|
|
Ecological species concept: -How is a species identified? -Pro
|
*Each species occupies its own ecological niche :)Useful for bacteria b/c many use the same resources and grow in the same habitat/environment |
|
|
1. What's a niche? 2. What happens with members in a given species within their own niche? 3. What happens if two organisms are similar? |
1. The unique set of all habitat resources that a species needs to persist and its interactions with the environment/other organisms 2. Members compete with each other for survival 3. Their needs overlap, which results in competition |
|
|
1. The competing organisms within a niche are likely to be of ...... species 2. How does reproductive isolation occur? |
1. the same 2. As a consequence of genetic changes when a species adapts to environmental conditions |
|
|
1. What are the two main reproductive isolating mechanisms? Define 2. What is an interspecies hybrid? 3. What is the opposite of an interspecies hybrid? |
1. *Prezygotic: Prevents the formation of a zygote *Postzygotic: Blocks the development of viable/fertile offspring 2. The offspring of parents from 2 different species 3. Intraspecies |
|
|
1. What are the 5 types of prezygotic barriers? 2. What are the 3 types of postzygotic barriers? |
1. Habitat, temporal, behavioural, mechanical, gametic isolation 2. Hybrid inviability, sterility and breakdown |
|
|
Describe: -habitat inhibition -temporal inhibition -behavioral inhibition |
1. When two species live in different habitats that are usually geographically isolated- prevents them coming in contact 2. They reproduce during different times of the year and day 3. Important in the choosing of a mate; sexual attraction between different species is limited due to the differences in behavior- vocalization, mating dance, appearance |
|
|
Describe: (Attempted mating) -Mechanical inhibition -Gametic inhibition |
1. Size and/or incompatible genitalia prevents mating 2. Gametes fail to fuse- important for species that release their gametes into the air/water |
|
|
Describe -hybrid inviability -hybrid sterility -hybrid breakdown |
1. When the fertilized egg doesn't grow past the early embryo stage 2. When the offspring is viable but is sterile 3. When the offspring is viable and fertile, but the subsequent generations have genetic abnormalities |
|
|
1. Why is inter-species hybridization uncommon in nature? 2. What is the underlying cause of speciation? |
1. B/c it takes a lot of energy and resources in order for this to happen 2. The accumulation of genetic changes that make separated populations different enough to be constituted as different species. |
|
|
1. What are the 2 patterns of speciation? Define 2. Which pattern is a (i) linear process (ii) branching process? |
1. *Anagenesis- linear- a species evolves into new species over the course of many generations *Cladogenesis-branched- A species diverges and evolves into 2 or more separate species. |
|
|
1. Which type of speciation type is the most prevalent method for cladogenesis? Define
|
1. Allopatric speciation- When some members of a species become geographically separated from the main group |
|
|
1. What does allopatric speciation prevent? 2. List the types of geographic barriers that could separate populations of species. |
1. Gene flow 2. Mountains, rivers, oceans, deserts |
|
|
1. What's another way of allopatric speciation? What is it called? 2. Describe 3. What is adaptive radiation? |
1. When a small population moves to a new location that's geographically separated from the mainland- Founder effect 2. Genetic drift and natural selection leads to the quick developments of differences= reproductive isolation 3. When a single species evolves into an array of different descendants that differ in form, function and habitat |
|
|
1. What's a hybrid zone 2. What happens over time when the two populations accumulate independent genetic changes? |
1. An area where two populations are able to come in contact and interbreed prior to reproductive isolation 2. Over the course of many generations, each population accumulates their own genetic changes- reduces their ability of interbreeding at the hybrid zone. Thus gene flow through the hybrid zone diminishes and leads to reproductive isolation. |
|
|
1. What's sympatric speciation? 2. What is the cause of sympatric speciation?
|
1. When populations of the same species live in the same habitat within the same range evolve into different species. 2. Abrupt genetic changes that quickly lead to reproductive isolation. |
|
|
1. What is one of the things that sympatric speciation changes with regards to reproductive isolation? 2. What are the 2 types of paces of speciation? Define |
1. Chromosome number 2. *gradualism- when each new species evolves continuously over long spans of time and large phenotypic differences are due to the accumulation of many small genetic changes *Punctuated equilibrium- Has a more sporadic tempo- when a species undergoes long periods of equilibrium and sudden bursts of changes
|
|
|
1. What has a strong effect on the rate of evolution regarding time? 2. What does evo-devo stand for? 3. What is evo-devo? |
1. Generation time 2. Evolutionary developmental biology 3. When you compare the development of different organisms in attempt to establish relationships between organisms and development mechanisms that bring about evo change |
|
|
1. What does evo-devo involve? (discovery) 2. What do changes in developmental genes affect? 3. What's the overall reason for the differences in a duck's webbed feet and a chicken's non-webbed feet? |
1. The discovery of genes that control development 2. The traits that are acted upon by natural selection 3. Differences in the expression of 2 cell-signalling proteins |
|
|
1. What's BMP4? 2. What's gremlin? 3. Which animal has gremlin? 4. What did mutations of BMP4/Gremlin expression provide? |
1. Causes cell apoptosis and die 2. Inhibits the function of BMP4 and causes the cell to live 3. Ducks- webbed feet 4. Variation |
|
|
1. In terrestrial setting, _____ feet are an advantage. 2. In aquatic environments, _____ feet are an advantage. 3. How did these type of feet come about? (NS) 4. What does this tell us about speciation? |
1. nonwebbed 2. webbed 3. Natural selection favoured and maintained the characteristic 4. Speciation could have also been caused by geographic isolation of habitats |
|
|
1. Why are Hox genes important? 2. Where are Hox genes found? 3. _____ ________ may have been a critical event in the formation of body plans 4. What's different among different types of animals regarding Hox genes? |
1. Imp in the evolution and speciation of body plans 2. In all cells 3. Genetic variation 4. The number and arrangement |
|
|
1. An increase in Hox genes ..... 2. What are the 3 lines of evidence support the importance of Hox genes with regards to body complexity?
|
1. increases the complexity of the body plan 2. -Hox genes control development - Increase in Hox, increases complexity of body plan - Hox gene evolution parallels animal evolution |
|
|
1. What's allometric growth and heterochrony? 2. E.g. 3. What do changes in growth rates in animals affect? 4. ________ in an adult is observed at an earlier stage in one species than another |
1. AG: Growth rates in different body parts differ. H: Evolutionary changes in timing and rate of developmental events 4. Reproduction |
|
|
1. What's paedomorphosis? 2. What's a major challenge regarding complex organs? 3. Researchers have discovered ___ different types of eyes 4. What did researchers think about eye development/evolution? |
1. The retention of a juvenile trait in adult organisms 2. Explaining how complex organs came into existence 3. many. 4. Thought that eyes may have independently arisen many different times during evolution |
|
|
1. What is Pax6? |
1. A master control gene that controls the expression of many other genes and influences eye development |
|
|
1. What are the eyes of Drosophilia and mammals derived from? 2. What would have happened if Drosophilia and mammalian eyes arisen independently? |
1. A modification of an eye that arose early during evolution 2. The Pax6 gene from mice would not be expected to induce the formation of eyes in Drosophila |
|
|
1. What did CD hypothesize about eye development/evolution? |
1. Hypothesized that the eyes from many different species all evolved from a common ancestral form consisting of one photoreceptor cell and one pigment cell. |
