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1. Evolutionary views of evolutionism.
Creationism: - Every single species has been created at the same time and they haven´t changed since its creation. –Natural world has been created by the intervention of a supernatural entity.
Various versions: Young Earth (less than 10.000 years, like in Bible). Intelligent design (efficiency of living beings is due to an intelligent designer).
Lamarck´s model: Species suffer changes along its evolutive history but there isn´t any nexus among different species, they all have an independent origin.
Darwin´s model: Species descend from shared ancestors and suffer changes since its origin.
Nexus among branches in the evolutionary tree by simbiogenesis processes and lateral genetic transference.
2. Typological (essentialism) versus population (Darwinian) thinking.
Essentialisms supports that any natural system can be classified in natural categories, each one defined by an essence that difference it from any other system and that it is set (fija). Different essentials are hierarchically ordered following a complexity pattern. Essentialism is divided on transmutationalism , where the only way a new living being can be originated is a macro mutation or leap, and transformationism where essence of inanimate world and organisms of animated world can suffer gradual changes along time. There are also two versions of transformationism depending on the causal agent: Leaded by environment , extern agent, use and disuse of an organ as response to ambient specific demands could create a gradual transformation of the attributes of that species, and orthogenetic principle or finalism where universe and all systems have a trend to change, to evolution, toward status each time more perfect.
Variational or populational point of view : There aren´t hierarchy. Species evolve because individuals are different since they were born, some arrive further because they are better adapted in the fight for survival and other leave more copies of their genetic characteristics because are better adapted to breed ( Natural selection ).
3. Homologous versus analogous traits.
Both show similar characteristics in function or appearance in different species.
Homologous traits are the traits developed by the species´s ancestors. They are inherited by a determined organism which belongs to the same evolutive branch as the ones which developed them. For example, all tetrapods have four limbs due to a common ancestor which possessed them.
Analogous traits have a different origin than homologous traits, but in order to adapt to an specific environment, they develop in the same way. For example, bird and bat wings share superficial similarities, but they weren´t inherited from a common ancestor: the origin is different, but the function is the same because natural selection shaped those individuals in order to develop wings and fly.
4. Vestigial versus atavistic traits.
Some species present traits which currently don´t have a specific function , or have been coopted onto a new function different to the original. In most cases, the loss of the organ or its functionality is caused by the lack of use it suffered over thousand or million years. This traits are considered vestigial if they are present in all the individuals of the same species. For example, the lack of existance of whales´ lowe limbs.
Atavistic traits are only present in a small number of individuals. They constitute "reappearances"of attributes which belonged to the ancestors of the species. (Such as the coxis projection from humans, similar to a tail).
In conclusion , both vestigial and atavistic traits are traits which have lost their functionality, but vestigial are present in all the individuals of the species, and atavistic only in few individuals.
5. Facts and inferences of Darwin´s theory of evolution.
Fact 1: Superfecundity , every individual can produce more offspring than necessary to replace progenitors when they die.
Fact 2: Stability on population size , there is a trend to reach a stable balance.
Fact 3: Limitation on food resources , fewer resources than necessaries to grow more than balance.
These three facts led to the first interference of Darwin, fight for existence , individuals are destined to race for available limited resources.
-Individuals are set by genotype and phenotype. It is the result of interaction between genotype and environment.
-Environment acts over phenotype and doesn´t affect the gens of the individual, so, characters acquired can´t be inherited. (Inheritance is hard)
-Genetic information is contained in some particles, genes, that retain the identity through generations, it means, they aren´t mixed with other genes, they are just combined between them.
-Genes mutate, normally with a slow rate, producing alternative stable shapes called alleles. Phenotypic effects can be very variable, unnoticeable or massive.
-Evolutive change is a population phenomenon, not individual.
-Change on proportion or frequency is the result of two mechanisms: genetic drift (deriva) and natural selection.
-Natural selection can generate differences among species that can be little or big. Adaptations are defined as features shaped by natural selection.
-Natural selection can amplify the range of original variations of a species increasing the frequency of alleles that recombinating with other genes that affect the same trait create new phenotypes.
-Populations are deposits of genetic variance and can evolve quickly when environment conditions change.
-Populations of any species differ among them in characteristics that have a genetic base. Many often these differences are adaptative and reflex the action of natural selection.
-Differences between species or populations are due to differences in multiple genes, many of them have a fewer phenotypic effect.
-Organisms with sexual breed species are set by groups of individuals that can interchange their genes.
-Speciation surge from a common ancestral species. Geographic isolation creates the differentiation of populations in the same species.
-Among living beings exist gradual variations in the characteristics attributed to species classified in the same genre or different. That means that main differences observed in upper categories can surge by accumulation of small differences and not by a mutation.
-Every organisms form a tree of life or phylogeny.
-Fossil register supports the idea of gradual changes.
Punctuated theory :
It is a theory crated to explain tempo and way of evolution. The main idea is that evolutionary change is not gradual but punctuated and occurs during cladogenesis and not anagenesis. It supports that history of lineages is characterised by long periods of evolutive calm or ecstasies (anagenetic).
Extended synthesis theory:
They support MS must be revised in order to incorporate the new developments. For example; non-genetic inheritance, environment as leader of genetic and evolutive change, relation of reciprocal construction between environment and organisms and the causality relation among phenomena that take place in different levels of biological hierarchy.
8. Mode and tempo of evolutionary change (anagenesis/stasis vs
cladogenesis, phyletic evolution vs speciation, gradualism vs
punctuationism, microevolution vs macroevolution).
Mode: Evolutionary change can happen when a species is branched (cladogenesis) or when it doesn´t (anagenetic). Mainly it happens in the first one.
Tempo: Evolutionary change can be gradual or intermitente. Mainly it happens intermitentemente en periodos acelerados de cambio, fllowed by periods of “evolutionary calm”.
9. Isolating barriers favouring speciation.
Two species are different if they are reproductive isolated. There are divers barriers, such us genetic mismatch. Reproducing isolating between populations lead to new species if it last in time enough time to produce genetic isolating.
-Precopula barrier: Prevent transmission of gametes between individuals. Ecologic isolation, individuals don’t match on time or space, and ethologic isolation, individuals can interact but don’t draw (no se atraen).
-Postcopula barrier. They interchange gametes but can’t create zygotes.
-Postcopula and postzigoto barrier.
10. Modes of speciation.
Disruptive selection: dando lugar a distribution of two average values of the attribute that are symmetric.
14. Naturalistic fallacy.
The naturalistic fallacy defends that everything that exists was designed to be the way it is. In other words, nature has designed us the way we are (with the good and the dark side) because it should be like that.
This is a mistaken belief. For example, street lamps were specifically designed to light up during night, but can also be used for other things, such as tying up bicycles.
15. Aptation, adaptation, exaption, pre-aptation and spandrel.
Aptation: Every attribute which is functional nowadays, it means, contributes to increase biological efficiency.
Adaptation: If actual function of the trait match with the original function.
Exaption: If any function doesn’t match with the original.
Pre-aptation: When a trait that already was functional acquires a new function.
Spandrel: A trait that originaly wasn’t functional but that in the end has a function.
16. Constraints on adaptation (suboptimality).
Structural constraints: They are organs that could be better but they aren´t because parts race for limited resources and the result is a trade-off.
Developmental constraints: Pleitropy a gen has more than one phenotypic effect, so some phenotypic expressions can be selectively advantageous, others neutrals and others harmful but if profitable effects are more vital to biological efficiency for the individual than those with negative effect, we will see that both ones will persist on the population. In epistasis is pretty similar but they are various gens which tend to be inherited in tandem, so features of every sign always persist if there is just one profitable trait.
Historic or phylogenetic constraints: E.g atavistic or vestigial traits.
17. Performationism versus epigenesis.
No entra
18. Haeckel´s biogenetic law or recapitulation principle versus von Baer
´s laws of development.
19. Recapitulation vs differentiation.
Recapitulation: The biogenetic law, the Haeckel´s law. Ontogeny recapitulates phylogeny. We can predict the ontogeny if we know the position of that organism in the tree of life. We develop the ancestral characteristics in the tree; we add the characteristics that evolved later. There is an order in which traits develop. In modern species, the reproduce old organs, then space is needed to add evolutionary innovations.
Differentiation: Ontogeny causes phylogeny. The only stages that species that are phenogenetically related will reproduce the same characteristics at the early stages (conservative development). The original traits are stable, but once individuals start developing new organs, anything can happen and there can be a inversion in the order in which ontogeny scale goes.
20. Progenesis versus neoteny.
Progenesis: The condition in which the sexual development in a modern species is accelerated in relation to what happens in ontogeny in the ancestral species.
Neoteny: The condition in which somatic development is ralentized in a modern species in relation to what happens in ontogeny in the ancestral species.
21. Linnaen versus evolutionary classifications of organisms.
The difference among thre Linnean classification of organisms and the evolutionary phylogenetic trees is that Carolus Linnaeus classified species in a hierarchical way. The hierarchy was inclusive, and organisms were classified by their resemblance to others. Linnaeus didn´t take into account the common ancestors of organisms.
For example, there would be differences among the bird lineage: A strictly Linnaean classification should place birds and no-Avian dinosaurs in two different categories.
- Random model : During a masive extinction relation between spieces´ physiology and probability of survivance is random.
- Different rules model : succesful species are those who take advantage on any apadtative characteristique different to those of the new enviroment or on non-
adaptative reasons.
29. The Red Queen and the Court´s Jester hypotheses of evolutionary
change.
The key difference is that Court´s Jester hypothesis focuses on random and non- directional of abiotic enviroment pressures while Red Queen´s hypothesissais that organisms can be adapted and at the same time continue adapting because neither the enviroment is estatic nor direction of changes. Also the first one focuses on abiotic enviroment and the second one on competition an coevolution between spieces of a biotic enviroment.
30. Testing the cone of disparity and the inverted cone of diversity.
Cone of growing disparity : evolution takes to an increased of disparity and complexity, it focuses on divergent nature of evolutive process, and encourages thinking evolution is a march forward.
Inverted cone of diversity: Path observed reveal the existence of a explosive beginning in the number of lineages, followed by the extinction of many of them and finally the diversification of species.
31. Predictability versus contingency.
Predictability accounts for changes which occur in normal circumstances. Departing from an initial set of information, we could be able to predict which are the individuals with most chances of surviving. This is directly related with natural selection: knowing which are the optimal traits which enhance an organism´s biological fitness, we can understand and prognosticate which will be the individuals which continue and represent the lineage.
In contingency, success or failure of species is not related with natural selection, or the traits these individuals have. Contingency accounts for unpredictable changes
which occur after catastrophes. Everything registered in fossils obey to multiple causes, but can only be identified "a posteriori".
32. Rejecting evolution as ladder of progress.
33. Major transitions in the evolution of life.
34. Primate phylogeny: Evolutionary trees (grades) versus
monophyletic trees (clades).
Evolutionary trees don’t have subfamily and tribes while cladists yes.
35. Diagnostic features of the primate order.
Locomotion: Hands and feet with finger oponible. Planes nails. Desplazamiento del centro de gravedad hacia las extremidades posteriors.
Sensitive organs: Desarrollo del tacto. Reduccion hocico y olfato. Vision binocular y estereoscopica.
Brain: Surcos laterals. Lobulo frontal, occipital y temporal. Mayor tamaño. Desarrollo del sistema visual.
Breed and path of history of life: Descenso testículos. Ovulación espontanea. Lactancia a demanda.
Aparato digestive: Ciego. Reduccion incisivos y premolars. Omnivoros.
36. Primates and the ecephalization quotient.
