What Prevents Horses And Donkeys From Hybridizing To Form A New Species?
In mules, horse & donkey chromosomes can not pair during meiosis to form viable gametes.
Which of the following are necessary for speciation to occur?
For speciation to occur, two new populations must be formed from one original population, and they must evolve in such a way that it becomes impossible for individuals from the two new populations to interbreed.
Which concept of species would be most useful to a field biologist identifying a new plant species in a tropical forest?
Bio101 Chpt 14 & 15
| Question | Answer |
|---|---|
| Which concept of species would be most useful to a field biologist identifying new plant species in a tropical forest? | morphological |
| The largest unit within which gene flow can readily occur is a ? | species |
Which of the following statements is true regarding the rate of speciation?
So, the correct answer is ‘Speciation only occurs slowly as small genetic changes accumulate from generation to generation‘
Is the mule an example of reduced hybrid viability?
Such reduced hybrid fertility can be due, for example, to problems arising within the hybrid during meiosis. The classic example of this phenomenon is the mule, a quite exceptional animal that nevertheless only tends to reproduce about “once in a blue moon”.
What are the three factors that cause speciation?
The factors responsible for speciation are: Geographical barrier. Natural selection. Genetic drift.
What are 3 causes of speciation?
The factors responsible for speciation are:
- Geographical barrier.
- Natural selection.
- Genetic drift.
- Large mutation.
What two factors affect the development of new species?
Reproductive isolation and environmental factors on the isolated population are also responsible for the formation of new species. Speciation can be driven by the evolution process that results in some changes in the gene is called a mutation.
What factors give rise to new species?
New species arise due to several factors:
- Natural selection.
- Geographical isolation.
- Reproductive isolation.
- Genetic mutation.
What conditions promote the development of new species?
New species more commonly occur when plants or animals cannot interbreed because of strong mate choice, and therefore they become isolated genetically. A less common type of speciation, called “sympatric,” occurs when a new species arises from a single population that has no geographic or physical barriers.
How does speciation happen?
Speciation occurs when a group within a species separates from other members of its species and develops its own unique characteristics. The demands of a different environment or the characteristics of the members of the new group will differentiate the new species from their ancestors.
Which is a part of the process of speciation?
In eukaryotic species—that is, those whose cells possess a clearly defined nucleus—two important processes occur during speciation: the splitting up of one gene pool into two or more separated gene pools (genetic separation) and the diversification of an array of observable physical characteristics (phenotypic
Which mechanism is most likely to result in rapid speciation?
A ALLOPATRIC SPECIATION
Allopatric speciation is widely believed to be the most likely mechanism of speciation in most animal taxa (Mayr, 1963, 1977). Several recent studies of cryptic species favor allopatric explanations of speciation (sticklebacks, Schluter and McPhail, 1992; mouse-eared bats, Arlettaz, 1995).
What prevents mules from producing offspring?
They have trouble making sperm or eggs because their chromosomes don’t match up well. And, to a lesser extent, because of their chromosome number. A horse has 64 chromosomes and a donkey has 62. A mule inherits 32 horse chromosomes from mom and 31 donkey chromosomes from dad, for a total of 63 chromosomes.
What prevent hybrid offspring from developing?
Postzygotic isolating mechanisms prevent hybrid offspring from developing or if the hybrid is born, it is infertile.
What causes reduced hybrid viability?
Reduced Hybrid Viability refers to a lower potential to survive for organisms whose parents have incompatible genetics, mostly because these parents mated despite being different species.
What are the 4 mechanisms of speciation?
There are four geographic modes of speciation in nature, based on the extent to which speciating populations are isolated from one another: allopatric, peripatric, parapatric, and sympatric.
What are the main drivers of speciation?
I.
The main driving forces appear to be stochastic — drift and/or mutation (both stochastic forces) drive the divergence between the forms, although sometimes very different selection pressures (natural selection) may be the dominant force.
What are the 5 ways species can become isolated and form new species?
There are five isolation processes that prevent two species from interbreeding: ecological, temporal, behavioral, mechanical/chemical and geographical.
Why can’t different species breed?
Because hybrid animals have parents from different species, the exchange of genetic information can cause many malfunctions in the chromosomes. This can result in the production of infertile sex cells and infertility.
What are two ways speciation can occur?
Speciation can occur either through allopatric speciation, when a population is geographically separated from one another, or through sympatric speciation, in which the two new species are not geographically separated.
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