Term
| What is Aposematism and what is a good example? |
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Definition
This is warning colouration to advertise unpalatability or toxicity.
(Rojas et al., 2013) looked at Female colouration/aposematism in the sexually dichromatic species of Dyeing Dart Frog. The females display colouration as a warning of unpalatability and noxiousness.
The dichromatism comes from stronger selection for mate colouration as they are the species that carries and deposits the eggs, and due to high levels of larval cannibalism, the faster the frog gets to the egg laying tree-fall gap spots, the more successful their offspring will be, so the brighter the males are, the quicker parasites will learn of their unpalatability and will avoid preying upon them. The aposematism works in synergy with the birth migration they perform, as apposed to the females which just have the selection of aposematism and so are duller in colour. |
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Term
| How does sex-role reversal occur and what is a good example is fish? |
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Definition
Sex-role reversal occurs when there is a skew in the sex-ratio or the females gain more fitness then the males from gaining multiple copulations.
(Flanagan et al., 2014) looked at the Gulf Pipefish, and the female extravagant colouration with a variation of larger or higher numbers of blue iridescent bands along the length of their lateral side. Females have higher potential reproductive rates than the males. Larger or more blue bands acts are seen as more attractive but they are in a tradeoff with egg fecundity. Findings showed larger bands led to more copulations but fewer eggs being transferred each time. |
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Term
| What is a sex-role reversal example in insets? |
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Definition
| (Hurst et al., 2000) looked at the Acreae encedon butterfly which are infected by the male embryo killing gram-negative bacteria Wolbachia. This creates a large sex-ratio skew and result in large lekking behaviour from the females to attract the few males that there are as 90% of the population are infected and will not produce male offspring. |
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Term
| What is an example of female ornamentation acting as an honest signal in insects? |
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Definition
(LeBas et al., 2003) looked at a species of Dance Fly (R. tarsata) which was ornamented with Pinnate scales of their hind legs and a inflatable abdominal sacs. This ornamentation is used because the females receive direct benefits from the mating as the males will bring nuptial gifts in the form of prey items, rocks and silk balloons.
The pinnate scales indicate honest fecundity signals but are prevented from fisherman runaway because they are in a slight investment trade-off with fecundity also.
Males will also attempt to judge the females on the maturity of there eggs as with no mature eggs it is wasted reproductive effort and with all mature eggs, the dance flies become very heavy and the mating flight becomes extremely energetically costly for the males, but the females are able to use their abdominal sacs to disguise their mature eggs and not give too much away. |
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Term
| What is a good example of honest signalling for fitness in primates? |
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Definition
| (Domb et al., 2001) looked at Olive baboons and the size of the perineal skin sexual swellings. The larger the selling indicated a earlier sexual maturity and high reproductive fitness and offspring success. Large perineal swellings indicate the female's lifetime reproductive value and therefore probable offspring success rate as to their increased experience with young. The males are able to choose the females based a lot upon this trait |
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Term
| What is an example of honest signalling to avoid unnecessary costly conflict in birds? |
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Definition
In the Eclectus Parrot, the females display bright red and blue plumage which indicates individual fitness and competitive ability. The vivid plumage can be viewed and judged by the other females who will be able to understand a rough hierarchy and dominance status from the brightness and upkeep of the plumage. The females perform nest guarding up to 11 months of the year and the males forage for them and the chicks with multiple males providing for singular females due to the polyandrous and polygynandrous mating behaviour. Tree hollows are very few and far between and therefore competition for them is high, with often fights to the death being observed and therefore strong plumage aids to avoid this cost. Like in the Zahavi (1975) handicap principle, the fittest females are able to keep their plumage in the best condition. This is to avoid conflict for quality nest locations. Conflicts will only occur when the two are very close matched and there is no submissive individual.
The potential benefit of the nest location must outweigh the cost of conflict and there must be good chance of winning, this is similar to the dove and hawk game. |
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Term
| What is the grandmother effect and what is a good example? |
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Definition
(Herndon et al, 2010) talks about the grandmother effect with a selection for life after stopping reproduction in humans because the females who have stopped reproducing are able to increase the reproductive fitness of their offspring by helping them with the raising of their offspring and allowing the daughters to reproduce again and maximise their reproductive success.
Herndon also speaks about the significant lack of cognitive degradation in humans and continued social cognition function in old age due to the grandmother effect and that the older individuals benefit their offspring more when they are more capable and able to provide good social care that will increase offspring success and the continued reproductive effort of the the grandmother's daughter.
Chimpanzees can reproduce all the way until they die which is around the age of 60 and show significantly higher rates of cognitive function degradation compared to homo sapiens.
(Hawkes 2016) modelled the idea of the grandmother effect evolving into an ancestral-ape population and with the fitness benefits that it would give the reproducing individual, with 1% of women living past beyond their fertility it would lead to a 40% by the end of their model, showing a selection upon this grandmother parental care trait. |
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Term
| What is the Trivers-Willard effect and what is an example from humans? |
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Definition
Good condition females are more likely to have male offspring and this is vice versa and also works with maternal investment too. This is because good condition males are more likely to have a high reproductive success and low condition males are not.
(Cameron et al., 2009) looked at the Forbes Billionaire list and found a sex-ratio skew of the women's offspring (billionaires or married to billionaires) of around 60% towards male offspring.
(Fujita et al., 2012) looked at the maternal investment of women of low socio-economic status and measured their maternal investment by looking at the fat content of their breast milk and found that the milk for daughters had significantly higher nutritional value/higher fat content than the milk produced by mothers with sons. |
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Term
| What is an example of controlled mate preference in humans? |
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Definition
(Feinberg et al, 2008) looked at the mate preference shifting in the menstrual cycle. The preference is towards masculinity of facial features, symmetry and voice during ovulation and then the preference for non-genetic resource, material and caring qualities in the rest of the cycle.
Feinberg et al. (2008) found that the contraceptive pill nulls the preference during to a lack of ovulation and therefore reduces a preference for the masculine qualities in a mate and therefore may lead to a reduction in these qualities in the modern male population with a percentage of 28% of reproducing women using the contraceptive pill (in the united states).
The masculine qualities that are preferred during ovulation are as a result of testosterone so the contraceptive use may lead to a lack of selection on testosterone levels in men |
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Term
| What is the Quality Quantity Trade-off in offspring production in humans? |
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Definition
(Lynch, 2016) looked at 200yrs of Icelandic birth and death records to find tradeoff existed between survival of the population and the birth rates. In decades of poor survival (low quality) the fecundity rates were elevated from a average (high quantity).
If the fertility preceded the mortality, the high fertility leads to increased birth rates and therefore increasing susceptibility to death through infection or in childbirth an therefore reducing offspring success too with no mother. Also higher reproduction rate may lead to lower parental care for each child and therefore reducing offspring success.
It may have been fertility boost occurring after the high mortality rates through some disease and then fertility rates are increased to compensate for the high mortality rates.
(Strassman et al., 2002) looked at the Dogon Tribe in Mali and found look at their hunter gatherer demographic. Optium birthrate was at around 10.5 births with a maximum of 4.1±0.3 offspring survival and deviations away from this optimal birth rate led to lowering of the maximum birth rate due to resource reduction, timings of births, chance and parental care reduction |
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Term
| What are the main sources for the believing in the aquatic ape hypothesis? |
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Definition
(Verhaeren, 1995), (Verhaeren, 2013), (Morgan, 1982) and (Hardy, 1960)
Aquatic Ape supposedly occurred 6-8 million years ago for 1-2 million years |
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Term
| What is the human hairlessness trait more likely to do with? |
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Definition
(Pagel et al., 2003) looked at the reasoning behind the human hairlessness most likely to be to do with ectoparasitic load which becomes a much larger problem when the Hominid ecology led to stable closed fixed home living around 1.8 million years ago. This is often only for parasites such as fleas which require a closed home living organism to complete their life cycle.
(Rogers et al., 2004) looked at the MC1R gene which codes for darker skin and looked for the date of mutation in this gene to indicate for the beginning of darker skin mutation which would alleviate the loss of hair and this dated back to around 1.2 million years.
This hypothesis working in synergy with the sexual selection hypothesis and the endurance running hypothesis possibly led to the loss of thick hair on the majority of our body. |
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Term
| Which paper discusses other hairlessness trait hypotheses? |
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Definition
(Rantala, 2007) looked at:
Cooling Hypothesis - Makes sense in endurance running synergy
Bipedalism - Makes sense in endurance running hypothesis for the decreased insulation for the savannah running and kept hair on our heads to prevent the sun effecting head too much
Sexually Selected Hypothesis |
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Term
| What other explanation is there for the bipedalism locomotion in humans other than AAH? |
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Definition
(Thorpe et al., 2014) looked at the idea that in ancestral apes they used a mixture of ape and human locomotion to move around their arboreal environment. They are more able to access food stuffs hanging from branches and such when in the bipedal position. And then from these ancestors, humans developed further complex bipedalism and chimpanzees and other apes went on to use more quadrupedal locomotion. Pan and Homo diverged around 7-10 million years ago.
Use of bipedalism may have come as we became more of an sharing altruistic species with sharing food and resources as bipedal movements increase carrying ability and load significantly.
Bipedalism can also be explained by (Bramble et al., 2004) endurance running and hunting hypothesis which explains that humans developed bipedal running as a energy efficient form of locomotion to increase endurance along with many other adaptations that allows us to chase prey to their almost exhaustion |
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Term
| How can increased brain size be explained by not the AAH? |
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Definition
| (Naverette et al., 2011) looked at the ecological differences and adaptations such as the increased human ability for tool assisted food preparation, cooking of food, fixed home living, cooperative feeding and breeding which all created a much larger net gain of energy from food and this allowed larger adipose deposits and free energy to invest into the energy demanding brain enlargement |
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Term
| How can olfactory bulb decrease be explained by not the AAH? |
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Definition
(Gilad et al., 2004) says more likely to do with the adaptation of tricolour vision which led to a much higher dependence on vision rather than sense of smell for signalling and understanding the environmental stimuli.
Odours can still be detected but the vision is just the most relied upon sense over it to detected surroundings along wth hearing |
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Term
| How can the origin of speech be explained by not the AAH? |
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Definition
(MacLarnon, 1999) looked at the evolution of the increased complexity and mechanical development of the thoracic innervation which is thought to have been imperative to breathe control and the creation of the larynx.
Is also supposedly derived around 1.6mya.
This can also link to the endurance running hypothesis with increased breathing control and higher mouth breathing and such, which breathing that is uncoupled with locomotive stride used for endurance running. |
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Term
| What is the endurance running hypothesis? |
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Definition
(Bramble et al., 2004) explains:
Hairlessness
Expanded Venous Circulation in Skull
Upright bipedal body with mouth breathing and uncoupled stride breathing for range of running speeds
Short muscular neck for head support
Developed achilles tendon and fatty heel to act as very functional shock absorber
Tall thin form for efficient body temperature control
Reduced arm length compared to all the primates, for efficient swing that still aids the running process and doesn't get in the way |
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Term
| What is the cost of sex and who first looked at it really? |
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Definition
(Maynard Smith, 1978) defined the twofold cost of sex
1) Males represent wasted reproductive effort as they take half of all resources for a species due to the Fisher's principle of 1:1 sex ratio, they contribute very little into producing the next generation
2) Anisogamous gametes means that an individual will only pass on 50% of it's own genome into the offspring, which is half the optimal amount for an individual as an individual wants the maximum amount of genetics in the next generation |
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Term
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Definition
(Muller, 1964) looked at the ratchet evolution of asexual organisms and their accumulation of deleterious mutations as there is no 'breeding out' process or recombination and random assemblage, mutations they obtain will be passed into their offspring
Organisms able to perform horizontal gene transfer due to a certain F plus or something are able to avoid this sometimes due to passage of other alleles that may effect the mutations but other than that it is just ratchet accumulation |
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Term
| What is an example of the cost of sex with parasites? |
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Definition
(Gibson et al., 2017) looked at the prevalence of P. antipodarum (a NZ freshwater snail) which has a sexual and asexual lineage. In stable and independent habitats, the asexual will out populate and outcompete the sexual lineage but in the presence of the microphallus parasite, the sexual lineage comprised 72% of the coexisting population.
This is predominantly to do with the RQH (van Valen, 1973) |
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Term
| What is a good example of the Red Queen Hypothesis and who created the RQH? |
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Definition
(van Valen, 1973)
(Mappes et al., 2004) looked at the RQH with two Psychid moth species which are both susceptible to a parasitoid wasp.
D. fennicala - Asexual
S. rupicolella - Sexual
S. rupicolella species was much higher in abundance than the D. fennicella when in coexisting population that were both effected by the parasitoid wasp |
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Term
| What does the damage from sex hypothesis add to why the sexual reproduction is a paradox and what is an example? |
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Definition
Physical damage cost from sex is the way that sec is not only consisting of the two-fold cost, but actual copulations and looking for a mate can be physically negative and incur large costs.
(Wiggly et al., 2005) looked at the male sex peptide (SP) produced in Drosophila species and the damage that it inflicts on females. SP stimulates egg production and decreases receptivity to sperm of OTHER males.
The accessory gland protein (SP) which is released in the male ejaculate will reduce the lifespan of the females and l;lifetime reproductive success, it's a display of selfish behaviour from the males to gain direct benefits of more concentrated self-progeny from the specific female.
(Real et al., 1996) looked at the increased mortality of female feral sheep on the French Antarctic Islands during the two rutting seasons in a year. The Females received high levels of harassment from the males which led to aggressive behaviour and female incurring injuries that often led to fatality. The females also showed extreme avoidance behaviour which drove them to dangerous cliffs to avoid male contact but also often led to slipping and falling to their death.
Feral and Wild sheep have a high potential reproductive rate and therefore attempt to copulate at a high rate. |
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Term
| What is the Fisher-Muller hypothesis and what is a good example? |
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Definition
This is the idea that sexual reproduction begets genotypic heterogeneity in a population and is the mechanism behind the RQH and also aids sexual animals to adapt to a heterogenous environment.
(Backs et al., 2010) looked at the rotifer species B. calyciflorus which is able to switch between asexual and seal reproduction. One population were put into an experimentally heterogenous and homogeneous environment each. In the heterogenous environment their was a a very high level of sexual reproduction performed compared of asexual, showing a preference for sexual reproduction in a changing environment in order to best adapt and utilise its habitat, although the B. calyciflorus did then fall back into asexual reproduction once it had become accustomed to the heterogenous environment. |
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Term
| Whaaaaat is an animal behavioural syndrome? |
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Definition
These are the groups of behaviours in a certain individual, certain behavioural tendencies will natural group to form a common behavioural syndrome. This behavioural syndrome will benefit and hinder the life history at different points
Will also usually be a certain form of context and environmental dependence on the effect that the certain behaviours have |
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Term
| What is a good example of animal personality tradeoffs? |
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Definition
(Smith & Blumenstein, 2008) created a meta-analysis of certain behavioural traits and how they influenced various life history qualities.
Bold behaviour = Higher reproductive success BUT lower expected lifespan
Shy behaviour = Lower reproductive success BUT longer predicted lifespan
No mono-directional selection on either of these traits and they are both vital areas of fitness and a balanced tradeoff
The trade-off is also environmentally context dependent and in fruitful areas, the shy behaviour creates a slower life history as an individual can afford to attempt to attain larger/better quality but less certain benefits. |
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Term
| What is a good example of Countervailing assortative and disassortative mating preference? |
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Definition
(Both et al., 2005) and (Dingemanse et al., 2004) looked at the Great Tit Parus major and the countervailing selection for mate preference.
Both et al. (2005) looked at 1yr old individuals found assortative mating at both extremes of the aggression and exploratory personality trait spectrum had the highest offspring success.
Low exploration and docile = larger fledglings and highest nesting success
High exploration and aggressive = best quality nest location and territory
Dingemanse et al. (2004) looked at adult birds and found that disassortative mating led to highest offspring success to produce offspring with highest intimidate phenotype for boldness and exploratory behaviour. This shows countervailing selection and also shows that their is selection for personality types and the behavioural syndromes of an individual do influence mate pairings and offspring success. |
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Term
| What is a good example of behavioural plasticity in an individual in birds and lizards? |
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Definition
(Norris et al., 2012) looked at the T. bicolor males' nest guarding based upon their levels of aggression and behavioural plasticity.
High aggression males had the best nest guarding ability overall, independent of any plasticity ability.
HOWEVER, the low aggression males' nest guarding ability was then influenced largely by their behavioural plasticity to change in the different environmental conditions (temperature in this case). The higher plasticity shown led to a change to aggressive behaviour in preferential conditions whereas low plasticity and low aggression led to no real change even in preferential conditions.
The plasticity in the preferential conditions was based upon minimal energy loss that these males could deal with, which they wouldn't be able to deal with in poor conditions
(Teyssier et al., 2014) looked at the Zootoca vivpara, Common viviparous lizard, looked at the environmental dependent plasticity of mate preference.
Females will generally prefer a bolder, higher activity mate as it links to the dominance in intraspecific interactions.
HOWEVER with the looming high levels of predatory risk, the female will chose a lower-activity, shyer male as a mate. This can also be linked to the copulation time, as high activity males will mate for longer and when in risk of predation, shorter copulation times are preferential |
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Term
| What is an example of an alternative mating strategy in birds that represents their behavioural syndrome and how is it controlled? |
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Definition
(Taylor et al., 2016) looked at the supergene control of the three male morphs of the Philomachus pugnax and the corresponding mating behaviour.
1) Territorial Male. Dark in colouration and highly territorial and aggressive, represents around 90% of the populations and contains no supergene control and is WT in reference to the other morphs
2) Satellite Male. Light in colouration, not territorial,low aggression and will move between the dark males territories performing mate attractive signals and performances and gaining mates this way. Represents around 10-20% of the population and is genetically controlled by an inverted supergene of around 100 genes that control the ontogeny of the individual.
3) Faeder Male. permanently mimics a female and will steal copulations from sneak mating. Represent around >1% of the population and is also controlled by a similar supergene.
Due to the inversion of the supergenes, these are unable to recombinate and are staple in the population |
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Term
| What is an example of frequency dependent personality dominance in mating tactics? |
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Definition
(Corl et al., 2010) looked at the side blotched lizards and discussed the 3 different morphs, all genetically controlled for the 3 distinct morphs.
Orange: Territorial and aggressive but will not mate guard
Yellow: Sneak maters
Blue: Mate guarders and mid-level aggression but will not guard their territory and cannot mate guard all of them. |
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Term
| What is a good example of sperm competition? |
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Definition
This is selection below the level of the individual although it is still in the benefit of the individual.
(Rowe, 2006) looked at the superb fairy-wren which is socially monogamous but highly sexually promiscuous and displays high levels of sperm competition for this reason. It is the competition for the quantity and quality of the sperm produced (based upon swimming speed and % motile sperm produced) which will give the sperm the best chance of getting to the sperm storage tubules and staying there.
There is high cellular selection which benefits the individual and acts as a selecting force for the individual too as the individual with the most high quality sperm will often by the parent. |
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Term
| What are Distorter Genes and why are you talking about them? |
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Definition
(Pressgraves, 2012) looked at the distorter genes (called segregation distorter genes (SD)) in the Drosophila melanogaster and discussed the literally selfish genes. They are involved in genomic conflict and will be able to hijack meiosis and induce dysfunctional spermatogenesis of the non-distorter gene carrying spermatids and so functional SD carrying sperm do not exist and so the SD gene ensures that it will be passed on to the next generation. This means that heterozygous individuals will definitely pass it on which is a large skew of the mendelian ratio predicted.
This is selection below the level of the individual only benefits the gene and not the individual. |
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Term
| What is an example of the heritability of epigenetic variation and why are you talking about it? |
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Definition
(Cortijo et al., 2014) looked the Arabidopsis thaliana and found that many of the epigenetic variation within the plant were under considerable epigenetic control from the epigenetic quantitive trait loci which allowed for phenotypic plasticity in changing environmental conditions. The EQTL were largely heritable.
This is being talked about because the epigenetic variation is thought to not to be selected upon directly through natural selection but the heritability of it means that it does influence the individuals ability to survive and therefore can be selected upon at the individual level |
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Term
| What is ecologic release, why are you talking about it and what is an example? |
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Definition
(Roches et al., 2011) looks at three mexican lizard species including the Little Striped Whiptail and the Eastern Fence Lizard which moved into a novel environment and showed large ecological opportunity due to the lack of predators and competitors and abundance of resources. Opportunity is there and then once the migration has occurred and the population begins to increased beyond their initial and usual carrying capacity, this is ecological release.
The process acts on individuals increased fitness and RS but also acts as a whole group selection mechanism because the whole population is able to increase at a much faster rate than there prior r rate |
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Term
| What is macroevolution and what is an example? |
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Definition
Macroevolution is the process whereby there a large selective pressures that act on the entire population of a species at the same strength for each individual and a natural evolution occurs of all members of a group simultaneously.
(Burin et al., 2016) looked at the development of omnivore in bird populations and process that evolution took to create omnivorous species in birds.
They found that the birds transition in omnivores from other dietary guilds at a much faster rate than the birds do in any other guild and it matches the rates of speciation in the other diary guilds. They also found that speciation rates were significantly low in the omnivores and extinction was significantly high yet omnivores make up 12% of bird species.
This is hypothesised because the omnivores would do worse in specific stable environments, and would outcompete the generalist omnivores but in unpredictable environments, the resource competition favours the generalist and will lead to transition of species into omnivorous dietary guild.
Burin et al (2016) found that the transition rate was occurring at a macroevolutionary rate and that the omnivorous dietary guild acts as a macroevolutionary sink. |
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Term
| What is a Just-so story and who derived this idea? |
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Definition
| (Gould & Lewontin, 1979) - Just so means looking at the adaptation of an animal and looking at its current function and then deriving that this is the reason that it was adapted in the first place, 'just so it could start doing this' which denies all scientific fact and just puts an easy explanation |
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Term
| What are multiple fitness peaks/rugged fitness landscape and what is evidence that this exists? |
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Definition
(Lacahpelle et al. 2015) looked at the C. reinhardtii colonies and split the propagated colony into multiple experimentally identical environments and saw how the generations would change and the evolution would occur. Each colony evolved in slightly different ways and gained similar fitness but showed variance in their adaptations. This is because there is no true singular fitness peak.
(Lens et al, 1994) performed a similar experiment on Escherichia coli and derived the explanation that sometimes there is more than one ESS. |
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Term
| What is an example of cryptic genetic variation? |
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Definition
(Rosner et al., 2013) looked at the cryptic genetic variation build up in a process known as canalisation which will occur in a environmentally stable state and where no variation is needed to occur in the phenotype.
This occurs in the A. mexicanus, the mexican cavefish which has a no eyed phenotype and yet they still posses all the genes for the eye in their cryptic genetic variation and this genetic variation will influence the phenotype and become translated into the phenotype in certain environmental conditions or with the addition of certain novel alleles. |
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Term
| What is an extended phenotype and what is an example? |
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Definition
(Dawkins, 1982) defined the Extended phenotype as the external effect that a certain gene will have, most likely on the environment. The genotype to create this extension is the adaptation and what is being selected upon in reproduction however the extended phenotype is what is being externally selected upon as it relays some aspect of fitness that will lead to growth, survival or reproductive costs or benefits!
(Kelley et al., 2012) looked at the extended phenotype of the male Bowerbird which makes a copulatory nest to attract a female mate. This nest is directly selected upon by the females to know the fitness of the male and whether he is a worthy male. It acts as a partly honest signal of fitness as only the fittest are able to create and guard high quality nests. |
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Term
| What is an example of a maladaptive trait in fish? |
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Definition
Maladaptive traits are adaptations which are not beneficial and can be costly in certain environmental conditions. This can most often come about in migratory organisms or organisms that are often in variable conditions and have not adapted in environmentally stable conditions. Most early seen in human intervened populations.
(Walsh et al, 2005) looked at the Atlantic silverside which has had a minimum size fishing policy on it which means that only the smaller individuals are being left in the populations by human intervention.
This leads to accidental artificial selection for maladaptive traits for the future repopulation to the carrying capacity of the Atlantic Silverside. The individuals left have reduced fecundity, egg size, larval size, growth rate, adult size and food consumption rate. These are all becoming maladaptive traits to the artificial conditions humans have created |
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Term
| What is an example of a maladaptive trait in amphibians? |
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Definition
(Shine et al., 2009) looked at the Cane Toad invasive species in Australia and looked at their traits that make them susceptible to pests, such as the meat ants, which pose no real threat to the native anurans
Cane Toad maladaptive traits to these are:
Diurnal behaviour which increases chances of crossing their path
Toads experimentally failed to notice the meat ants let alone avoid them when moving about
Toads relied on crypsis when being attacked as a predator avoidance but is ineffective against meat ants |
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Term
| What is an example of an exaptation in primates? |
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Definition
Exaptations are adaptations that evolved for one particular reason or by chance and now serve another function or fulfil a useful function at all.
(Pievani et al., 2011) looked at the scalloped connection in primates teeth which connects the enamel and the dentine. This scalloped enamel-dentine junction developed as a natural epithelial folding in ontogeny but largely reduced the sliding of the dentine and enamel in the tooth which greatly reduces wear and tear of the teeth. It also significantly reduces the stress on teeth during mastication.
This adaptation is largely beneficial and is very unlikely to be selected against but it came about through no direct selection process. |
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Term
| What is the key thing to remember about optimality modelling and game theory? |
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Definition
Optimality modelling is the process by which we try to understand the selective processes that exist in the forming of certain traits and adaptations. When the model is tested and the trait is far from being optimal, there are two explanations.
1) the process is mid selection and is currently under directional selection although this is rare in most stable species
2) we, the scientist, does not fully understand all of the selective processes that are existing to control the trait size, quality, quantity and there may be tradeoffs we do not see and ignored variables acting on the selection process.
Optimality Modelling is the process by which we quantify the traits qualities and inefficiencies in the ABSENCE of all competing and influencing organisms
Game Theory is the process by which we understand the traits in the presence of competing organisms, predators and prey and understand the influence these variable have on each other and the selective processes that occur because of them |
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