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Chapter 24 The Origin of Species - Coggle Diagram
Chapter 24 The Origin of Species
Reproductive Isolation
Prezygotic Barriers; stops mating or fertilization if mating does occur
temporal-when they have different seasons such as one is nocturnal and the other isn't or one mates in spring and the other is in the fall
mechanical- when something physically prevent them from reproducing like a shell for example
behavioral- when one breed does something to attract their sexual partner but their partner doesn't like what they do
gametic- when the egg can't be fertilized by a different species
habitat-living in the same area but in different parts of that same area
Postzygotic Barriers; prevent hybrid zygote from developing into a viable fertile adult
reduced hybrid fertility- when hybrid offspring can be born healthy but are not fertile
hybrid breakdown- when the first couple of generations are good, healthy, and can reproduce but as they go down they start to breakdown and die
reduced hybrid viability- when hybrid offspring have a low chance of survival
Species Concept
Without Isolation
-sympatric speciation is when a new species forms while organisms still live in the same environment
Definition of Species
Morphological Species Concept is all about the shape and anatomy of a species
Biological Species Concept is when the same species reproduce and their offspring can reproduce (all about sex)
Phylogenic Species Conceptis a species as the smallest group of individuals that share a common ancestor forming one branch on the tree of life
Ecological Species Concept is how members of a species interact with nonliving and living part of their environment
With Isolation
-allopatric speciation is when a population forms a new species while being geographically isolated from their parent population
bottleneck
founders
Hybrids
Is defined as offspring from 2 species
Hybrid Zone is an overlap between groups; an example of this is 2 species of frogs living in the same area and overlapping
-fusion is when offspring are better or as good as the parent population
reinforcement is when offspring is worse than parent population
Degradation is when offspring have a longterm accumulation of defects
Time and mechanisms for speciation
Punctuated Equilibrium means long changes of inactivity followed by sudden changes; such as how the dinos were here for a long time and then suddenly gone
Genes
Junk DNA is used to describe portions of the genome not used to code for proteins
Ploidy
diploid is an organism that has 2 complete sets of chromosomes
haploid is an organism that has a single set of chromosomes
polyploid is when a species originates from an accident during cell division that results in extra sets of chromosomes
~autopolyploid is an individual that has more than 2 chromosomes sets that are all derived from a single species, itself
~allopolyploid a fertile individual that has more than 2 chromosomes sets as a result of two different species interbreeding and combining their chromosomes
HOX genes guide cells to develop into structures appropriate locations in the embryo
Gradualism means slow changes which is supported by microevolution