Speciation 300 BIOLOGY GB 2014
Speciation
300 BIOLOGY
GB
2014
Introduction
Complete the Moodle pretopic Quiz: http://learningon.theloop.school.nz/moodle/mod/quiz/view.php?id=68826
http://www.pbs.org/wgbh/evolution/educators/teachstuds/svideos.html
Achievement StandardEvolutionary processes involve the following biological ideas:
Role of mutation
Gene flow
Role of natural selection and genetic drift
Modes of speciation (sympatric, allopatric)
Reproductive isolating mechanisms that contribute to speciation (geographical, temporal, ecological, behavioral, structural barriers, polyploidy)
Patterns such as divergence, convergence, adaptive radiation, co-evolution, punctuated equilibrium, and gradualism.
Scientific evidence for evolution, which may include examples from New Zealand’s flora and fauna, will be selected from:
fossil evidence
Comparative anatomy (homologous and analogous structures)
Molecular biology (proteins and DNA analysis)
Biogeography.
The BasicsTerms: ______________ – carry the genetic information required for cell growth,
functioning and replication
_____________ – alternative form of a gene (creates variation)
_____________– all the alleles of a population
_______________– movement of alleles in and out of a population
______________ - evolution of new species, new species cannot reproduce with old species
_____________ – change in the base sequence in DNA, must occur in gametes to be passed on. Creates totally ___________ phenotypes.
Changes in Allele Frequencies ___________________– massive loss of alleles due to natural
disaster, leaves a non representative population
________________– small non representative group migrate to a new habitat
_____________– random loss of alleles due to chance in a small population
Tasks Complete workbook pages 171-173
Complete Worksheet: Gene Frequency Questions
Complete Gene Pools Moodle Quiz
http://learningon.theloop.school.nz/moodle/mod/quiz/view.php?id=68828
Kahoots Genetic Drift Basics
https://play.kahoot.it/#/?quizId=a4f952ba-9dcb-4995-a247-75d30a8af5d8
Natural SelectionOrganisms _________suited to their environment mate and pass on their ____________ to the next generation ____________ the number of these helpful genes in the ____________, meanwhile those unsuited do not mate and those genes ___________ from the gene pool.
_____________ selects against the two extremes and favors the middle (2)
____________ selects against one of the extremes (3)
___________ selects against the middle and favors the two extremes, this can lead to speciation (1)
Complete Workbook pages 164-170
Variation Differences between individuals in a species, caused by
differences in the ____________________
The more _______________ in a species the ___________ chance that some of the species will ____________changes within their environment
Variation is _________during sexual reproduction, meiosis (crossing over, independent assortment, segregation) immigration and mutations
Variation must occur within the ________ in order to be passed on
Variation is ______________ by natural selection, genetic drift (bottleneck effect, founder effect), emigration and natality.
Cline Speciation
Cline Speciation – ________________of different but interbreeding organism
Ring Speciation – continuous gradient that moves in a ___________ and _________up at the two ends at which point the two species rarely interbreed as have _____________________
Tasks Read pathfinder pages 11-15, answer questions 2, 4, 6, 7
Complete Moodle Natural Selection Quiz
http://learningon.theloop.school.nz/moodle/mod/quiz/view.php?id=68847
Complete the following online activities
http://ats.doit.wisc.edu/biology/ev/ns/t2_a1.htm
http://ats.doit.wisc.edu/biology/ev/ns/t3_a1.htm
Speciation One species evolves into ______________that can no longer
__________________
Usually occurs as a result of __________to new ecological niches and in response to the occurrence of new variations within the species that make an organism better able to ________________ _______________________________
Speciation
There are three ways in which new species can evolve:
1. _________________________Occurs within _______________as
a result of polyploidy more than ________ sets of
chromosomesUsually occurs in ______________
Speciation2. _______________________ Occurs when a new species arises in the
______ territory as the parent species Often occurs as a result of
__________________(ie finches living in top of trees vs forest floor)
3. __________________________________ Occurs when a new species evolves as a
result of being _______________ from the parent species
_____________ territory Often occurs when there is some kind of
____________________________disturbance
Tasks:
Complete worksheet: More Speciation Questions
Complete workbook pages 178-181
Complete this online activities:
http://ats.doit.wisc.edu/biology/ev/sp/t1_a.htm
http://ats.doit.wisc.edu/biology/ev/sp/t2_tabs.htm
Kahoots: Speciation
https://play.kahoot.it/#/?quizId=f29c2dc5-9acb-4615-96c8-8f5c887a6573
Polyploidy and Aneuploidy Poly – many, _______________ = more than
one set of chromosomes
Aneu – one, ___________________ = one chromosome is represented three times instead of the usual two (one from each parent)
_____________________ usually separate during meiosis to create two gametes with haploid (n, half the original) chromosomes
Non Disjunction __________________– when homologous pairs of chromosomes
fail to separate during meiosis the _____________ can end up with: Having two copies of a single chromosome (________________) Having a missing chromosome (_____________________) Having 2 whole sets of chromosomes (___________________) Having NO chromosomes (zygote is unlikely to form in this case)
Offspring formed from gametes with the incorrect number or chromosomes can end up having: 3 or more of an individual chromosome – ________________
3 or more sets of chromosomes – ____________________
Polyploidy generally only occurs in plants and can be ____________________ as often results in bigger better crops, or seedless crops (infertile plants have no seeds!)
Aneuploidy in the sex chromosome in humans can result in:Turners Syndrome – __________Klinfelters Syndrome – _____________
Aneuploidy in an autosomal chromosome in humans can result in:________________– trisomy 21 – 3 number
21 chromosome______________– trisomy 18 – 3 number
18 chromosomes
Types of Polyploidy Polyploidy can result in both ______________________ offspring
In order to be fertile an organism needs to have an ____________number of chromosomes (so they can line up in homologous pairs and separate during ______________)
___________________– organisms with multiple sets of chromosomes from the _________________ species
____________________– organisms with multiple sets of chromosomes from _________________ species
Auto polyploidy Eg a potato produces gametes with ____________ (more than one set of
chromosomes) and mates with another potato giving rise to a new potato with ______________ (3 sets of chromosomes but all from the potato family, and likely to be _______________________ number of chromosomes)
Often occurs when plants _____________
If _________ gametes have undergone non disjunction then the offspring will be fertile as it will be have an _________ number of chromosomes -_______ or tetraploid, happens when plants self fertilize
If only one gamete has undergone _____________it will result in infertile offspring as there will be an uneven number of chromosomes – 3n or ________
Allopolyploidy Eg a wheat plant fertilizes a rye plant
If the offspring has an uneven number of chromosomes due to ______________ having occurred in one of the gametes then the offspring will be _____________
If the offspring has an _________ number of chromosomes due to non disjunction occurring in both gametes then the offspring will be _________________
If the uneven numbered gamete manages to fuse with another normal gamete and a plant with _____________ chromosomes arises then it will be a fertile hybrid – this usual occurs as a result of self fertilisation.
_____________ – made from two different species
Tasks
Complete workbook pages 161-163 and 182-184
Isolating Mechanisms
In order for a new species to arise it must not be able to reproduce with the parent species.
Prevention of reproduction can occur in several ways:
1. Pre Zygotic (______________a zygote is formed) _____________________– separated by space, river, ocean, mountain, road etc
____________________–reproducing at different times of year, active at different times of day
______________ – live in different ecological niches
_______________– different courtship behaviours
_______________– reproductive genitalia incompatible
________________– pollen grains don’t grow pollen tubes
2. Post Zygotic (once zygote has formed) Polyploidy – multiple sets of chromosomes, in an uneven number so
that offspring are infertile
____________– zygote is aborted as has chromosomal incompatibility
_______________– off spring survives but is sterile – mule
_________________– hybrid is fertile but its offspring are sterile
Tasks Complete workbook pages 173-178
Complete workbook pages 190-198
Complete Isolating Mechanisms Jigsaw Worksheet
Complete Moodle Quiz Isolating Mechanisms
http://learningon.theloop.school.nz/moodle/mod/quiz/view.php?id=68829
Complete the following online Activities:
http://ats.doit.wisc.edu/biology/ev/sp/t2_a.htm
Kahoots Isolating Reproduction
https://play.kahoot.it/#/?quizId=18bcd549-da76-465e-b365-74c9b13239f9
Evolution _________ - the gradual change in species over long periods
of time resulting in establishment of a new species, (lots of speciation's occurring one after the other over millions of years!)
_______________ of alleles exists within the population
The organisms are exposed to a _____________________such as a changing environment
Those with ____________ phenotypes are more likely to survive and reproduce while those with less favorable phenotypes have less chance of surviving and reproducing. ___________________________________
Each generation will be _________________________to the current environment.
Patterns of EvolutionSpeciation or evolution can occur in a variety of ways:
___________________
Common ancestor, but no longer look the same
Humans and apes from a common primate ancestor
______________________
Unrelated ancestor, but look similar due to similar selection pressures due to living in similar environment
Whales and fish look the same as both live in water but NOT related
__________________
Unrelated ancestor, dissimilar environment but still look similar
Adaptive radiation
____________________________
Species which are unrelated but have a close ecological relationship exert selection pressures on each other
Predator /prey eg flowers grow to allow certain birds to pollinate, birds develop long beaks so can get pollen
Tasks Complete worksheets – cut and paste match, Patterns of Evolution - Divergence
Read Pathfinder pages 18-22, answer questions 1-9 (these are similar to what you will get in the exam!)
Read pathfinder pages 25-28, complete questions 1-6
Complete Moodle Quiz Patterns of Evolution
http://learningon.theloop.school.nz/moodle/mod/quiz/view.php?id=68842
Complete the following online activities:
http://ats.doit.wisc.edu/biology/ev/sp/t3_a1_a.htm
http://ats.doit.wisc.edu/biology/ev/sp/t3_a1_c.htm
Rate of Evolutionary Change ________________________
Slow progressive change over time
___________________________ Generally slow change but with periods of rapid
evolution Caused by rapid and extreme changes to the
environment Eg ice age, volcanic eruption
Complete workbook pages 184-190
Evidence for Evolution _____________ comparison to current day
species
_______________________
________________ structures Same origins but different function
Forelimb bones of birds, humans, whales, bats
_________________ structures Different origins but similar functions
Wings of bats, birds, and moths
___________________ The more similar embryos are of different species the less time has
past since they diverged
_____________________– geographical origins of current species distributions
______________ – similarities between DNA and proteins
Complete workbook pages 153-160
Tasks Read Pathfinder pages pages 18-22, answer questions 1-9 (these are similar to what
you will get in the exam!)
Read pages 25-28
Complete Evidence for Evolution Jigsaw worksheet
Complete Moodle Quiz Evidence for Evolution
http://learningon.theloop.school.nz/moodle/mod/quiz/view.php?id=68848
Complete Evolution NZ Examples worksheets
https://play.kahoot.it/#/?quizId=8e8173c1-cde2-4238-8de3-dc2651e875f4
https://play.kahoot.it/#/?quizId=51375569-7666-4ac2-b57b-6c6dd5da647f
https://play.kahoot.it/#/?quizId=e74b4ec1-9155-4ca2-82b4-a6da4f291982
https://play.kahoot.it/#/?quizId=f3d74de6-5ae6-4480-8aec-cafc1224ce84
The End