Assessment Schedule 2005 Biology: Describe patterns of evolution (90717)

Transcription

1 NCEA Level 3 Biology (90717) 2005 page 1 of 4 Assessment Schedule 2005 Biology: Describe patterns of evolution (90717) Evidence Statement Q Achievement Achievement with Merit Achievement with Excellence 1(a) Describes the process of divergent evolution. Eg: Divergent evolution occurs when one species develops into two or more species (in different habitats). 1(b) Describes an appropriate change that might have led to the speciation of northern rätä from southern rätä. Requires some sort of appropriate separation geographical. Eg: During the time this speciation occurred New Zealand was warming up after an ice age. The north of New Zealand has been warmer than the south during this period. Sea levels were rising, isolating areas of land from each other such that the North and South Islands formed. North and South Island were originally one land mass separation by Cook Strait. Explains how change in New Zealand during this time may have led to geographic isolation and subsequently the development of reproductive isolating mechanisms. Must be an Explanation. Eg: During this time New Zealand s climate was warming, which caused sea levels to rise. The islands formed would have had slightly different climates (warm north, cold south), which would mean different selection pressures. This led to the development of reproductive isolation / new species. Needs to be some explanation of selection pressures. New Zealand Qualifications Authority, 2005 All rights reserved. No part of this publication may be reproduced by any means without prior permission of the New Zealand Qualifications Authority.

2 NCEA Level 3 Biology (90717) 2005 page 2 of 4 Q Achievement Achievement with Merit Achievement with Excellence 1(c) Describes ONE of the processes: adaptive radiation, punctuated equilibrium or gradualism. Eg: Adaptive radiation is the evolutionary diversification of related species, from a single ancestor, to occupy different niches. Gradualism is thought to occur when species slowly and steadily diverge from one another over time. Punctuated equilibrium is thought to occur when there are long periods of little change in species, and then short bursts when there is rapid change, often associated with speciation. Note, the description must have key characteristics. Explains how ONE of the processes adaptive radiation, punctuated equilibrium or gradualism, is linked to the situation shown by Metrosideros in the Pacific. eg Justify why it is Punctuated Equilibrium why it is not Gradualism. Eg: Adaptive radiation is the evolutionary diversification of related species, from a single ancestor, to occupy different niches. So when climate and geological changes occurred, the ancestral species Southern rätä radiated out to occupy the new niches formed. Gradualism is thought to occur when species slowly and steadily diverge from one another over time due to gradual changes the ancestral population encounters. This does not seem to occur with Metrosideros because there are not regular and gradual changes in speciation. Punctuated equilibrium is thought to occur when there are long periods of little change in species and then short bursts when there is rapid change often associated with speciation. This seems to occur with Metrosideros because there are three periods of rapid change and dispersal shown. Needs to relate to the resource material. Discusses how Metrosideros shows adaptive radiation with punctuated equilibrium, rather than gradualism, probably due to climate changes. Discussion needs to include both, and needs to relate to the resource information provided. Eg: Adaptive radiation is the evolutionary diversification of related species, from a single ancestor, to occupy different niches. So when climate and geological changes occurred the ancestral species Southern rätä radiated out to occupy the new niches formed. Its adaptations are widely suited to the wind pattern changes that would accompany an ice age such as occurred 2 million years ago, or to the colonisation of new volcanic islands. Such events favour the idea of punctuated equilibrium rather than gradualism for Metrosideros, which it shows at times of rapid warming or cooling of the climate. Punctuated equilibrium is thought to occur when there are long periods of little change in species, and then short bursts when there is rapid change, often associated with speciation. This seems to occur with Metrosideros because there are three periods of rapid change and dispersal shown. It shows times of change when there is rapid warming or cooling of the climate. It does not show the idea of gradualism, which is thought to occur when species slowly and steadily diverge from one another over time due to gradual changes the ancestral population encounters. With Metrosideros there are not regular and gradual changes showing gradual speciation. Needs to be a discussion that relates evolution of new species to environmental, climatic changes.

3 NCEA Level 3 Biology (90717) 2005 page 3 of 4 Q Achievement Achievement with Merit Achievement with Excellence 1(d) Describes a feature of convergent evolution in relation to the pollinators of Metrosideros. Eg: Convergent evolution occurs when very different species, develop similar features. Needs to imply they are very different species that are not related The honey-eater birds and shorttailed bats have similar tongue adaptations to get nectar from Metrosideros must indicate same food source or similar. Explains how the similar adaptations of the tongues of the pollinators of Metrosideros are, an example of Convergent Evolution. Eg: Convergent evolution occurs when very different unrelated species develop similar features. This is seen here because the honey-eater birds and short-tailed bats have developed similar tongue adaptations to get nectar from Metrosideros, which they both pollinate. (Need to have definition of convergent evolution similar structure in bird and bat to get nectar). 2 Describes a relevant feature of instantaneous speciation. Eg: If a new individual forms that has an extra set of chromosomes (it cannot interbreed with its parents). Polyploidy makes individuals with multiple sets of chromosomes (that can t interbreed with each other). Extra chromosomes is not enough. Explains how instantaneous speciation can occur that polyploid speciation is sympatric speciation. Eg: An individual gets an extra set of chromosomes due to a malfunction of meiosis. The new organism can self-fertilise but can t breed with the parent stock. Eventually a population of these organisms grow that cannot breed back with the parent stock and so they are a new species. Instantaneous speciation by polyploidy occurs in the same geographical area as the parent population so it is also sympatric speciation. Need both these ideas. Discusses how instantaneous speciation can occur, what reproductive isolating mechanisms develop and why it is considered sympatric speciation. Eg: An individual gets an extra set of chromosomes owing to nondisjunction / failure of the chromosomes to separate during meiosis. The new organism can selffertilise but is reproductively isolated from the parent stock. The reproductive isolating mechanism that prevents the parent stock and the new species interbreeding is a post-zygotic isolating mechanism. The hybrids are sterile because they have odd numbers of chromosomes and cannot form gametes by meiosis because it breaks down. They may self-fertilise, and if they are plants without the sex determining chromosomes, a population of these organisms grow that cannot breed back with the parent stock. So they are a new species in a very short time. This is said to be instantaneous speciation and because it occurs in the same geographical area as the parents it is sympatric speciation as well. Need both these ideas.

4 NCEA Level 3 Biology (90717) 2005 page 4 of 4 Judgement Statement: Achievement Achievement with Merit Achievement with Excellence Total of THREE opportunities answered at Achievement level (or higher). 3 A Total of FOUR opportunities answered. TWO at Merit level and TWO at Achievement level (or higher). 2 M + 2 A Total of FOUR opportunities answered. ONE at Excellence level and TWO at Merit level and ONE at Achievement level (or higher). 1 E + 2 M + 1 A

5 NCEA Level 3 Biology (90717) 2006 page 1 of 3 Assessment Schedule 2006 Biology: Describe processes and patterns of evolution (90717) Evidence Statement Question Achievement Achievement with Merit Achievement with Excellence 1(a) Description recognises that there would be a change in allele frequency, eg Alleles coding for longer beaks would become more common in the population. 1(b) Describes the key concepts in the operation of natural selection: There is genetic variation within the species, individuals with longer beaks can gain more food and be reproductively successful. Individuals best adapted to reach the seeds of the balloon vine tend to leave more offspring. Explains how longer beaks would give an advantage & so be selected for such that in time the population would change Some soapberry bugs have longer mouthparts than others and this trait is heritable. Bugs with longest mouthparts can better exploit the new food source (less competition, better fed).these bugs will become more prevalent in the population. Evaluates or compares the adaptive advantage of inherited longer mouthparts as a means to access a new and increasing food source over that of the short beaked bugs. There is a change in the population with an increasing prevalence of balloon vine as an invasive weed. Introduced balloon vine presents a new feeding opportunity not available to native insects. Soapberry bugs with longer mouthparts become more common in the population in areas with balloon vine. 1(c) Gives a correct definition of speciation, eg Speciation is the process of forming new biological species. 1(d) Recognises that speciation involves the loss of ability to interbreed to produce fertile offspring, or reproductive isolation, but gives no further comment related to the bugs. Explains that the long-beaked population will be a new species only if: The bugs with longer mouthparts and feeding on balloon vine were unable to breed with the short-beaked bugs on other food sources. gene flow cannot occur between those with longer beaks and those with shorter beaks. 2(a) Correctly defines adaptive radiation as, eg The term given to a range of species evolving (radiating) from an ancestral species to exploit new niches.

6 NCEA Level 3 Biology (90717) 2006 page 2 of 3 2(b) Identifies that uplifting creates geographical isolation or new habitats and different selection pressures, eg rising Southern Alps new alpine habitats available. different selection pressures in these new environments. those individuals with characteristics better suiting them to these environments more likely to reproduce successfully. Explains origins of new cicada species in terms of allopatric speciation or genetic variation with differential reproductive success, eg Ancestral cicada popn spread into new habitats. Genetic variation within popn some variants better able to exploit new niches. Successful variants leave more offspring, pass alleles to offspring. Genes / alleles controlling characteristics that enhance successful exploitation of the new niche increase in frequency with each generation. Genetic differences eventually reproductive isolation, & speciation. 2(c) Recognises that process may have begun with allopatry from a shared ancestral species: Cicada populations isolated during glacial periods, evolved into different species while allopatric. that sympatric speciation occurred in the one location as speciation occurs from a shared ancestral species. Explains that either speciation process is driven by different selection pressures: Niche differentiation, competitive exclusion or Gauses principle may be used to explain sympatric speciation. Explanation of allopatry extends to explain presence of species today in same location due to break down of geographical isolating mechanisms. Extends answer to evaluate present-day situation of maintenance of separate species in terms of reproductive isolation, eg different songs different timing of emergence different reproductive behaviour. 2(d) Describes either gradualism or punctuated equilibrium. Gradualism is thought to occur when species slowly and steadily diverge from one another over time. Punctuated equilibrium is thought to occur when there are long periods of little change in species and then short bursts of speciation when there is rapid change in the environment or selection pressures. Explains how data supports punctuated equilibrium by referring to species or groups of cicadas given.

7 NCEA Level 3 Biology (90717) 2006 page 3 of 3 2(e) Recognises that the birds were exposed to similar selection pressures or convergence. Explains similarities in terms of natural selection: Feeding opportunities are greater for those with long curved beaks able to extract bugs from trunk crevices and this means reproductive success. This adaptation evolved independently in unrelated birds exploiting similar ecological niches where bugs are found in crevices of tree trunks. Judgement Statement Biology: Describe processes and patterns of evolution (90717) Achievement Achievement with Merit Achievement with Excellence FIVE questions answered correctly. Minumum 5 A SEVEN questions answered correctly, including at least FOUR at Merit level. Minimum 4 M + 3 A SEVEN questions answered correctly, including at least FOUR at Merit level and at least ONE at Excellence level. 1 E + 4 M + 2 A

8 NCEA Level 3 Biology (90717) 2007 page 1 of 2 Assessment Schedule 2007 Biology: Describe processes and patterns of evolution (90717) Evidence Statement Q Achievement Achievement with Merit Achievement with Excellence 1(a) Description of coevolution recognises there will be a mutualistic relationship /benefit to both the bat and food plant to ensure reproductive success. 1(b) Defines the key concepts in the operation of Natural Selection: there is variation in the species, individuals with longer tongues can gain more food and be reproductively successful -individuals with longer tongues leave more offspring. Explains that flower (corolla depth) and bat (tongue length) would evolve together Bats with longer tongues get more food energy and have greater reproductive success. Deep flowers provide food for bats and ensure successful pollination or reduced predation from other species. 1(c) Defines adaptive radiation as a new species evolving from a common ancestor to exploit newly available niches with new adaptations. Explains the impact of specific geological history. Glaciers or mountain building splitting populations into smaller groups. The exposure to different selection pressures e.g. as East and West differentiate due to mountain building. Evaluation of reproductive isolation is discussed with reference to the way that species reproductive isolation or genetic differences are maintained for those species using pre or post-zygotic mechanisms to justify the outcome. 1(d) Identifies that the separated populations of this species are the start of the speciation due to poor gene flow. Explains that the two distinct populations may become reproductively isolated via physical separation (allopatry) or niche differentiation (sympatry) to become two new species.

9 NCEA Level 3 Biology (90717) 2007 page 2 of 2 Question Achievement Achievement with Merit Achievement with Excellence 2(a) Identifies that the different Libertia species have evolved through a series of polyploidy events thus doubling chromosome numbers. 2(b) Recognises that L. paniculata has a multiple diploid chromosome number. Explains that failure of homologues to separate (nondisjuction) in meiosis has effected 2n gametes and that fusion of 2n gametes has produced 4 n offspring Amphiploidy following fertilisation has formed 4n individuals. 2(c) Recognises that L. peregrinans has been formed by gametes having multiple sets of chromosomes. Explains that L. peregrinans has evolved through a series of polyploidy events as demonstrated by the artificial hybrids between L. ixioides and L.grandiflora. 2(d) Describes adaptive radiation As a new species of Indigo bird that has evolved from a common ancestor and defines punctuated equilibrium as new Indigo birds species evolving in a short space of time following a period of stasis. Reasons are given for the indigobirds showing high species diversity (adaptive radiation) that their rapid development occurred in response to the increase in Finch species and thus increase in new niches (to parasitise). Data from the diagram is used or referred to. 2(e) Defines sympatric speciation as New species evolving in the same geographic area due to niche differentiation or reproductive isolation due to host finch song recognition. Explains that new Indigo bird species have formed and remain reproductively isolated due to differences in song or courtship behaviour learned from the Finch host species. Relates the initiation of a new Indigo bird species to evidence of a new song of a new host which will then be imprinted on the young of indigo birds that have parasitised this new host. Evaluates reproductive isolation by linking the new courtship behaviour as specific, in that it mimics the new host. Judgement Statement Achievement Achievement with Merit Achievement with Excellence FIVE questions answered correctly. Minimum 5 A SEVEN questions answered correctly, including at least FOUR at Merit level. Minimum 4 M + 3 A SEVEN questions answered correctly, including at least FOUR at Merit level and at least ONE at Excellence level. 1 E + 4 M + 2 A

10 NCEA Level 3 Biology (90717) 2008 page 1 of 3 Assessment Schedule 2008 Biology: Describe processes and patterns of evolution (90717) Evidence Statement Q. Achievement Achievement with Merit Achievement with Excellence ONE (a) (b) (c) (d) (e) Describes what is likely to happen to the fish population due to this pattern of selection eg: Fish populations will come to be made up of smaller individuals. Fish that reproduce / mature earlier will become more common. Smaller fish are more likely to survive / reproduce. Identifies the pattern of evolution ie Divergent evolution. Identifies the type of speciation ie Sympatric speciation. Describes ONE way these species are reproductively isolated, eg: flowering at different times / seasons Gamete incompatibility Hybrid infertility / breakdown Temporal isolation of flowering Polyploidy gives different numbers of chromosomes / non-homologous chromosomes. Describes the pattern of evolution shown, eg: Divergence / Adaptive radiation. Explains what is likely to happen to the fish population due to this pattern of selection eg: Fish populations will come to be made up of smaller individuals because the genes / alleles for larger fish are constantly and selectively removed from the breeding population / gene pool. Fish populations will come to be made up of smaller individuals as they survive to reproduce more frequently than the larger fish. Explains how these species are reproductively isolated, eg: If they flower at different times of the year they cannot pollinate each other. There is gamete incompatibility so if the pollen reached the egg the gametes cannot fertilise / develop into a new plant. Hybrid infertility due to odd number of chromosomes / can t go through meiosis / cannot make gametes. Polyploidy gives different numbers of chromosomes so even if gametes fuse / pollen fertilises other species the embryo cannot develop to maturity.

11 NCEA Level 3 Biology (90717) 2008 page 2 of 3 (f) Describes how this group of species could have evolved considering a geological event a selection pressures, eg: The southern alps being formed created new habitats / niches. Isolated populations have different selection pressures. During formation of the southern alps groups of Pachycladon may have been geographically isolated. Explains how this group of species could have evolved considering geological events and a specific selection pressure, eg: The southern alps being formed created new habitats / niches. These had their own selection pressures such as different soil types which acted on the populations causing them to adapt to their specific niches causing genetic / phenotypic differences sufficient that the two populations can no longer interbreed. Discusses how this Pachycladon group of species could have evolved considering TWO geological events and specific selection pressures, eg: An ancestral Pachycladon population originally in Australia was able to disperse to NZ. The southern alps being formed and lowered sea levels during an ice age created many new cooler / wetter habitats / niches. The new niches had different selection pressures such as different rock substrate acting on the populations. Adaptation to these different niches caused genetic / phenotypic differences sufficient that the two populations can no longer interbreed. As there is reproductive isolation between the populations speciation has occurred. TWO (a) Identify the form of selection operating in these populations e.g. Sexual (mate) selection / disruptive selection / non-random mating. (b) Describes the implications of the female s mate preferences for the future evolution of the yellowthroats, eg: The populations will continue to become more different from each other genetically / in allele frequencies / phenotypically. The different preferences by females will cause reproductive isolation between the populations. Female choice of mate may act as a behavioural / reproductive isolating mechanism. Females mate choice differences may lead to speciation / divergent evolution. Explains the implications of the female s mate preferences for the future evolution of the yellowthroats, eg: The populations will continue to become more different from each other phenotypically due to different mate selection leading to speciation as there is no gene flow and the populations develop reproductive isolating mechanisms. Different mating preferences could lead to reproductive isolation between the two populations due to an accumulation of genetic differences between the populations. Discusses the implications of the female s mate preferences for the future evolution of the yellowthroats, eg: Due to the different (mate) selection pressures of yellow throats in New York and black masks in Wisconsin populations will continue to become more different from each other. This changes allele frequency between the populations. Over time the accumulation of genetic differences between the populations will lead to reproductive isolation so speciation has occurred. (c) Identifies the form of speciation ie Allopatric speciation.

12 NCEA Level 3 Biology (90717) 2008 page 3 of 3 (d) Describes the evolution of the Hoplodactylus geckos in NZ (in relation to the impact of the geographical isolating mechanisms the evolution of reproductive isolating mechanisms), eg: Explains the evolution of the Hoplodactylus geckos in NZ (in relation to the impact of the geographical isolating mechanisms the evolution of reproductive isolating mechanisms), eg: Discusses the evolution of the Hoplodactylus geckos in NZ by considering how at least TWO geographical isolating mechanisms led to the evolution of reproductive isolating mechanisms, eg: Populations were isolated on lowlying islands which caused allele frequencies to change. Mountain building formed new habitats with new selection pressures. NZ populations were separated for long periods of time enabling reproductive / behavioural isolation. Populations were isolated on lowlying islands during interglacial periods which caused allele frequencies to change leading to gecko speciation. NZ gecko populations separated for long periods of time when NZ was a series of low-lying islands subject to different selection pressures. Due to the populations adapting to the different environments reproductive isolation mechanisms have developed. When NZ was a series of low-lying islands the gecko population was isolated and subjected to different selection pressures. These populations accumulated genetic differences and developed reproductive isolating mechanisms (such as post/pre-zygotic). Sea levels dropped / mountain building / volcanic activity created new habitats / into which gecko populations could disperse. Different selection pressures in each would have caused further reproductive isolation between populations. Judgement Statement Achievement Achievement with Merit Achievement with Excellence Total of SIX opportunities answered at Achievement level or higher. 6 A Total of at least SEVEN opportunities answered with THREE at Merit level or higher. 3 M + 4 A Total of at least SEVEN opportunities answered with TWO at Excellence level and ONE at Merit level or higher. 2 E + 1 M + 4 A

13 NCEA Level 3 Biology (90717) 2009 page 1 of 3 Assessment Schedule 2009 Biology: Describe processes and patterns of evolution (90717) Evidence statement Q Evidence for Achievement Evidence for Achievement with Merit Evidence for Achievement with Excellence ONE (a) G. fortis: stabilising selection on beak size. G. fortis: directional selection with respect to shape. G. scandens: directional selection on both parameters. G. scandens: directional selection on beak size. G. scandens: directional selection on beak shape. Any ONE of the above five options for (a). (b) EITHER Changes in environment could decrease food supply by: / Competition for food is caused by / Prolonged drought leads to: - Fewer plants / - Plants producing fewer seeds / - Fewer pollinators - Starvation - Dying of thirst (ONE idea needed.) The drought lead to the availability of food becoming a significant selection pressure / the drought lead to increased competition for food. Changes in beak shape / size are probably driven by competition for resources (beak shape / size related to type of food eaten). Evidence of Ref to graphs. More effect on scandens than on fortis / Comparison of changes in each species. Competition leads to natural selection / selection pressure. Immediate selection in form of changes to climate / drought. Drought leads to (Bottleneck Effect) reducing / changing allele / gene frequency. The drought of the 1970s would have killed off many plants decline in seed availability. Many finches would die of starvation / thirst those that survived were better adapted at getting available food sources. Competition for available food could then drive changes in beak dimensions reduced competition (character displacement). Possible that beak size and shape evolve together. The differences with respect to beak size and shape have increased between scandens and fortis Key idea is that differences in beak size and shape allow for different ecological niches and therefore reduce competition. This in turn leads to the continuation of both species Divergent Evolution. TWO (Temporal isolating mechanisms) species separated (only )by timing of breeding / egg laying / fertility Describes the situation. EITHER temporal differences in egg laying The laying time means that broods appear 6 weeks apart and chicks are unlikely to mingle / compete for resources. Reduced interspecific competition between chicks for resources such as food, space. Allows chicks to exploit seasonally available food which in turn could act as a selection pressure for divergent evolution. BOTH of the EITHER / Merit points must be discussed to gain Excellence. One idea is needed from each set of points. Candidate needs to consider the evolutionary significance of both ecological factors and other reproductive isolating mechanisms. For both Merit and Excellence, no exact wording is required, just the ideas expressed in included points.

14 NCEA Level 3 Biology (90717) 2009 page 2 of 3 Reduced interspecific competition between adult birds for nesting sites, food for themselves, food for chicks. Increased competition between species if environmental conditions are such that one group of chicks damages the habitat for the other. No other mechanism: species interfertile and fertile hybrids do occur / speciation is tenuous due to success of interbreeding / minimal difference between species due to success of interbreeding Genetic differences are not enough to guarantee isolation, as the two species are known to produce fertile hybrids on occasion, ie the species are so close that if the 6- week difference was lost, they would probably revert to a single species. This suggests a relatively recent origin for the 2 species. If the temporal difference persists, other genetic differences may accumulate to the point where they are incapable of any interbreeding. The idea that the evolutionary pathway could go either way either returning to a single species or divergence. For Merit an explanation of the evolutionary significance of temporal isolation with respect to competition for resources the significance of genetic similarities and / or differences on the evolutionary process. Any ONE of the points above can be expanded on to gain Merit.

15 NCEA Level 3 Biology (90717) 2009 page 3 of 3 THREE Any correct reference to phylogenic tree: Eg: Species formed as a result of divergent evolution / adaptive radiation NZ gecko come from a single common ancestor NZ and New Caledonian geckos come from a common Australian ancestor NZ gecko separated from New Caledonian gecko 64 million years ago any other similar statement. A single source population for NZ geckos (as shown in phylogenetic tree). Gecko divergent evolution / adaptive radiation caused by: Geological changes include - tectonic activity, uplift creating mountain ranges, ice ages, melting of land bridges, formation of geographical barriers such as rivers, mountains, oceans. (ONE example needed) Climatic changes include Temperature, humidity, composition of atmosphere, sea level changes, changes in rainfall eg. Colder in the south than the north / high altitude colder than low.(one relevant example needed) Divergence / speciation of geckos within NZ followed access to a variety of possible ecosystems resulting from both climatic and geological changes. (include one relevant example of each type of change eg: temperature, altitude) As for Merit plus: Any TWO of: Lack of predators in NZ may underlie higher divergence than in other regions. New Zealand has a greater number of species because of larger landmass and greater latitudinal variation.( Or vice versa for New Caledonia). Eg the long thin nature of New Zealand in the North South direction creates a wide variation in temperature. This provides a large variety of ecological niches and allows for the existence of clines or demes. Similarly the presence of a central mountainous area running North South along the country, creates a variety of possible niches. New niches and selection pressures in the different regions both largescale (between countries) and within NZ. Example given of at least one selection pressure and it s resulting evolutionary change. Allopatric and / or sympatric speciation occurs due to existence of reproductive isolating mechanisms. Eg: Recent appearance of alpine and forest geckos related to recent mountain-building events in NZ. Judgement Statement Achievement Achievement with Merit Achievement with Excellence 3 A 2 M + 1 A 1 E + 1 M + 1 A

16 NCEA Level 3 Biology (90717) 2010 page 1 of 3 Assessment Schedule 2010 Biology: Describe processes and patterns of evolution (90717) Evidence Statement Q Evidence for Achievement Evidence for Achievement with Merit Evidence for Achievement with Excellence ONE (a) ONE of: Describes types of speciation (a) Eg penguins could undergo speciation in different places (allopatric speciation) or in the same place by occupying different niches/habitats (sympatric speciation). BOTH types needed Describes isolating mechanisms for each type (a) Eg, geographical boundaries could keep birds from interbreeding. ONE of: Temporal differences may result in breeding at different times. Different mating rituals may isolate groups of birds. Physical differences may make mating impossible. Hybrid sterility may inhibit breeding. Hybrid inviability may stop interbreeding. Hybrid breakdown may prevent interbreeding. Polyploidy. Description of types or isolating mechanisms explanation of how this leads to speciation for both. (m) Any 2 RIMs from (a) can be used for M but must have gained A by including both allopatric and sympatric example. Eg penguins based on different islands are unlikely to mate. Penguins that live in the same place but have different niches will become adapted for their niche. In both situations gene flow is limited, and over time different selection pressures / accumulation of genetic differences result in enough change, so that they cannot interbreed. Discussion links sympatric and allopatric speciation to isolating mechanisms and gives examples of species for at least one and how post-zygotic and pre-zygotic mechanisms work together. (e) Eg sympatric speciation is where species don t interbreed due to niche differences. For instance, they may breed at different times, which means that there is limited gene flow. Eventually, genetic changes will mean they cannot interbreed. Snares and Rockhopper is an example of allopatric speciation, as they live on different islands. Because they now have different crests, the Rockhopper and Snares penguins don t recognise each other as a mate, which is good, as if they did, the offspring may be infertile, so they have wasted time and energy. (b) Names and describes convergent evolution. (a) Eg convergent evolution is where similar selection pressures result in similar adaptations in species from different ancestors. Names convergent evolution and explains it, using the examples. (m) Eg the penguin and seal have different ancestors/ unrelated but both occupy a niche that involves swimming, so both have separately evolved flippers. (c) Describes coevolution. (a) Eg species evolving in response to each other. Explains coevolution using the example. (m) Eg as the slowest penguins are predated on, the more agile penguins pass on their alleles, so penguins become more agile overall. As a result, the most successful seals will be the ones that can catch these more agile penguins, and so the more successful seals will pass on their alleles, so both species become more agile. A 1Xa M -2Xm E 1Xe

17 NCEA Level 3 Biology (90717) 2010 page 2 of 3 TWO (a) Defines natural selection. Eg natural selection is where the best suited individuals have a greater chance of reproductive success. The survival of the species is promoted. (a) Not the survival of the individual Not survival of fittest on it s own Explains the natural selection process. (m) Eg individuals with more suited / better adapted phenotypes will compete more favourably than others that are less suited and are more likely to reproduce, passing on their favourable alleles. Favourable alleles will increase in frequency within the population. (b) Describes the process of speciation identifies a relevant isolating mechanism. (a) Eg when the ancestral species arrived in New Zealand, plants with suitable adaptations moved into available niches. As the species spread across New Zealand, populations became isolated due to mountain barriers and climate differences, as mountain ranges like the Southern Alps developed. Must specifically mention geological or climatic features or an example as per resource material Explains how speciation is likely to have occurred and links it to at least one isolating mechanism relevant to the Dracophyllum example. (m) Eg when the ancestral species arrived in New Zealand, due to variation within the species, plants with slightly different adaptations filled a variety of available niches, leading to adaptive radiation. Populations of the Dracophyllum ancestor became isolated due to mountain barriers and climate differences as mountain ranges, such as the Alps, and glaciations occurred. Certain alleles / phenotypes became selected for in isolated populations, leading to speciation. Discusses how environmental changes over the past 8million years and natural selection have contributed to evolution of Dracophyllum through speciation / adaptive radiation. (e) Eg when the ancestral species arrived in New Zealand, due to variation within the species, plants with slightly different adaptations filled a variety of available niches, leading to adaptive radiation. Those that adapted successfully could reproduce. Populations of the same species became separated and small founder populations became established. They became isolated due to geological and climatic changes, for example, as the Southern Alps formed and colder glaciations occurred, resulting in a range of habitats from alpine to warm, damp lowland forests / east coast and west coast differences. Over time changes in the allele frequencies / mutations occurred, sympatric speciation such as polyploidy incidents occurred, allopatric speciation due to isolation occurred, resulting in a number of separate species being formed due to reproductive differences A 1Xa M 1Xm E 1Xe

18 NCEA Level 3 Biology (90717) 2010 page 3 of 3 THREE (a) Evidence can be from Three (a) or Three (b) Identifies / defines PE Eg long periods of stasis with sudden speciation/periods of evolution leading to genetic change. (b) Answer must make reference to diagram. (a) Answer for (a) can be used for (b) even without ref to diagram (a) Any two of: Defines Gradualism. Eg gradualism is slow genetic change over a long period of time. (a) Defines Punctuated Equilibrium. Periods of stasis with sudden speciation/periods of evolution leading to genetic change. This can carry across from 3(a) Describes factors favouring PE Eg introduction to a new niche / sudden environmental change favours PE. (a) Describes factors favouring Gradualism Eg gradually changing conditions (no sudden major events) favours gradualism. (a) A _ 1Xa Explanation links definition to how conditions lead to one of PE / gradualism (m). Eg when conditions change very slowly, the selection pressure is not very intense. This means that while some individuals will have a greater chance of reproductive success, any change in allele frequency will occur over a long period. This results in gradual change of the species. A lack of sudden environmental changes or a lack of change in niche availablility leads to a slow rate of evolutionary change gradualism. : Sudden changes in niche availability or environmental changes can lead to periods of rapid evolutionary change - punctuated evolution. M 1Xm Compares the conditions for both PE and gradualism relating to the example (e). Eg when conditions change very slowly, the selection pressure is not very intense. This means that while some individuals will have a greater chance of reproductive success, any change in allele frequency will occur over a long period. This results in gradual change of the species, such as in milliganii. This is gradualism. Whereas with the introduction of a species to a new place, such as Dracophyllum to New Zealand, the one species has a number of new niches, each with its own selection pressures causing sudden speciation, which is punctuated equilibrium. E 1Xe AM = M AE =E Judgement Statement Achievement Achievement with Merit Achievement with Excellence 3 A 1 A + 1 M 1 A + 2 M 1 A + 1 M + 1 E

19 Version 7 NCEA Level 3 Biology (90717) 2011 page 1 of 3 Assessment Schedule 2011 Biology: Describe processes and patterns of evolution (90717) Assessment Criteria Q Achievement Achievement with Merit Achievement with Excellence ONE (a) Describes the pattern as punctuated equilibrium or divergent evolution or adaptive radiation. Describes a process for the pattern Eg: New / empty niches are available / mountain building / glaciations / ice ages / sea level changes. Punctuated equilibrium is identified as the pattern; and the processes leading to punctuated equilibrium are explained. Eg: Short bursts of evolutionary change happened as new niches opened up / environment change / mountain building / ice ages / sea level changes followed by periods of stasis / no change in the environment. (b) An event leading to speciation is described. Eg: Parrot populations became separated by mountains / hills / geographical barriers. A process that has led to speciation is described. Eg: Gene flow between populations stopped / do not mate / cannot mate / reproductively isolated / no interbreeding (in Nestor). Eg: The environment has little / no change (for Strigops). Eg: Gene flow continues as the population does not separate (for Srigops) Eg. Individual populations would not easily become isolated due to birds restricted movement / inability to fly. Eg. No competition leads to no speciation / changes (Remember competition is a selection pressure) Events and processes leading to speciation in Nestor are explained. Eg Populations of Nestor spread into different areas due to competition for resources (food, nesting sites, mates). Geological isolation (mountain building / glaciation / sea levels rising) follows and opens up new niches / habitats. Due to new niches there will be different selection pressures. Reasons why there has been little evidence of speciation in Strigops are given. Eg: Strigops is in an environment with little or no changes. The selection pressures remain the same therefore no speciation occurs. Gene flow remains between groups Individual populations would not easily become isolated due to birds restricted movement / inability to fly. Separate species are not likely to have formed as gene flow continues. Discusses ecological divergence in Nestor the lack of divergence in Strigops. Eg: Populations of Nestor spread into different areas due to competition for resources (food, nesting sites, mates) / Geological isolation (mountain building / glaciation / sea levels rising) follows and opens up new niches / habitats. Due to new niches there will be different selection pressures. New alleles / phenotypes / traits / adaptations selected for. Isolation of populations resulted in no gene flow, leading to eventual speciation. Strigops is in an environment with little or no changes. The selection pressures remain the same therefore no speciation occurs. Gene flow remains between groups Individual populations would not easily become isolated due to birds restricted movement / inability to fly. Separate species are not likely to have formed as gene flow continues. 1 a 1 m 1 e

20 Version 7 NCEA Level 3 Biology (90717) 2011 page 2 of 3 TWO (a) Describes convergent evolution. Eg: Species have evolved from different ancestors Species have evolved due to similar selection pressures. Explains convergent evolution. Species arising from different evolutionary lines / without a common ancestor (must indicate no relation in the past) similar phenotypes / adaptations / traits / structures / analogous structures have evolved due to occupation of similar niches / having similar selection pressures / similar habitats / similar environmental conditions. (b) Any TWO of: Adaptive radiation is described. Eg: Many species from a common ancestor / one species evolve due to many different habitats / niches being available. Polyploidy is described. Eg: Polyploidy results in the offspring plant having a duplicate number / extra set of chromosomes / change in the number of chromosomes sets. Polyploidy results when a malfunction / error occurs in meiosis Polyploidy gives rise to instant speciation. Geographical isolation is described. Eg. Geographical isolation can happen when populations become separated due to environmental events such as mountain uplift / tectonic plate movement / sea level changes / ice ages. Polyploidy geographical isolation are explained as processes that result in adaptive radiation. Eg: Polyploidy is due to nondisjunction / failure of chromosomes to separate during meiosis resulting in an extra set of chromosomes in the offspring. This leads to instant speciation / no gene flow / new species. Geographical isolation can happen when populations become geographically separated due to environmental events such as mountain uplift / tectonic plate movement / sea level changes / ice ages so gene flow / interbreeding cannot happen between populations. Discusses how both polyploidy and geographical isolation occur and have likely impacted on the evolution of Hebe in New Zealand. As for merit for BOTH processes. Discusses the impact of each process on the adaptive radiation of Hebe. Eg: Polyploidy is due to nondisjunction / failure of chromosomes to separate during meiosis resulting in an extra set of chromosomes in the offspring. This leads to instant speciation / new species. The offspring cannot reproduce with is parent species / can only reproduce vegetatively / asexually and so gene flow does not occur. Geographical isolation can happen when populations become geographically separated due to environmental events such as mountain uplift / tectonic plate movement / sea level changes / ice ages so gene flow cannot happen between populations so becomes reproductively isolated. Physical barriers may change the environment / habitat / niche, which alters the selection pressures. New phenotypes / adaptations lead to new species. 2 a 2 m 1 e

21 Version 7 NCEA Level 3 Biology (90717) 2011 page 3 of 3 THREE Any TWO of: Identifies viable selection pressures that could isolate South Island populations. Eg: Distance / competition for food / courtship behaviour / water temperature / predation etc. Identifies the evidence that the South coast population is a founder from the West coast population. Eg: DNA of South and West coast populations are the most similar / small size of the South coast population South coast population contains fewer alleles that represent a small proportion of the West coast population Identifies the significance of little or no gene flow Eg: Populations do not encounter each other and so mating does not occur so reproductively isolated / no interbreeding The 3 South island populations will become 3 species. Explains how a selection pressure operates on the South Island populations. Eg: Competition for resources may have spread populations apart. Those with favourable adaptations / phenotypes to the changes survive and pass on their phenotypes / adaptations to their offspring and over time become isolated. Explains how the DNA evidence indicates the South coast population is a founder from the West coast population Eg: Genetic / DNA evidence / Small size if South coast population suggests populations are becoming geographically isolated. There are greater similarities between South Coast and West Coast populations, suggesting a more recent separation and that the South Coast population is a founder / break-away from the West Coast population Explains how reduced / no gene flow can impact on the three South Island populations. Eg: No gene flow results in the three populations becoming reproductively isolated and so low interaction which leads to further reproductive isolation. Evolution processes occurring between the South Island populations are explained and discussed. Eg: Selection pressures such as competition for food, distance, water temperature and courtship has led to geographical isolation of the three South Island populations. Genetic / DNA / (see Guinea Pig 1 for example of small size of population) evidence suggests populations are becoming geographically isolated. There are greater similarities between South Coast and West Coast populations / differing frequency of alleles present / same mtdna present, suggesting a more recent separation and that the South Coast population is a founder / breakaway from the West Coast population. The significance of the finding that there is little or no gene flow between the three South Island populations is discussed. Eg: No gene flow results in the three populations becoming reproductively isolated / having reproductive isolating mechanisms (RIM) which eventually leads to 3 species. Judgement Statement Achievement Achievement with Merit Achievement with Excellence 2 A 2 M 1 E + 1 M

22 NCEA Level 3 Biology (90717) 2012 page 1 of 3 Assessment Schedule 2012 Biology: Describe processes and patterns of evolution (90717) Assessment Criteria Question Evidence for Achievement Evidence for Achievement with Merit Evidence for Achievement with Excellence ONE The evolutionary relationship is named or described. Eg, co-evolution. Changes in one species are directly related to changes in the other. The nature of the coevolution is described. Eg, the ants have over time relied on acacia for food and housing and acacia has survived being attacked by insects, browsing mammals and epiphytes. A realistic outcome is described if the ant numbers are reduced. Eg, the acacia numbers may also reduce / lose their protection / cease producing food bodies / become extinct etc. Must name or describe relationship / pattern of evolution as Coevolution. either Explains why the co-evolutionary relationship has developed. Eg, both species have co-evolved to fill the mutualistic relationship due to selection pressures and have experienced increased survival / reproductive success / advantages. The ants living on the acacia have been more successful and have been more likely to survive and go on to reproduce, passing on their phenotypes / traits / alleles / adaptations. Likewise, the acacias with large hollow thorns and specialized food sources to feed the ants have gained a survival advantage and have passed on their preferential and specialised phenotypes / traits / alleles / adaptations. A realistic outcome is explained if the ant numbers are reduced. Eg, if the ants were to become reduced in numbers over time, the acacia would no longer be protected by the ants against insects etc Would have to compete against other plants for space, light etc as they would no longer have the ants to clear the surroundings. Explains evolutionary relationship between the ant and the acacia Eg, in a co-evolutionary relationship, changes in one species are directly related to changes in the other, so a reduction in numbers of ants will have a direct effect on the acacia. This acacia species could then be attacked by herbivores and other insects and reduce in numbers. discusses what could be expected to happen if the ant numbers reduced. The surviving population will have particular phenotypes / adaptation / alleles that aid their survival in the absence of the ants, which are selected for such as poisonous leaves, stinging thorns, very thick spikey vegetation that is hard for herbivores to browse on, They could develop another relationship with a different insect that offers similar protection. The acacia may lose its Beltian bodies over time, as there is no use for them and they cost the plant energy to produce so they would be selected against This acacia species may not adapt and so may face extinction Evaluate the evolutionary relationship between the bullhorn acacia and the stinging ant including explains how / why the relationship developed Eg, both the ant and the acacia have benefited from the relationship, which has resulted in the survival and reproductive success of each species, ensuring the beneficial adaptations / alleles / phenotypes / traits have been selected for and passed on to the next generation. Thus, the mutualistc relationship may have developed because the selective pressures of each species (e.g. link to original benefits - the Beltian bodies and their nectar, as food for ant or the hollow thorns providing shelter to ants protection) were beneficial / provides an adaptive advantage for the other species. A = 2 a M = 1 m E = 1 e