NA | NA |
How to deconstruct public arguments | 1 Sentience 2 Sexism and Hierarchies |
TrpA1 | Essential channel for nociceptor (pain receptor) in vertebrates
TrpA1+ TrpC1 = pain receptors, part of common opisthokont heritage, universal existence among all metazoans |
TrpC1 | Shared across drosophila, arthropod and vertebrrates |
Cnidarians | Earliest animals, with bona fide, neuronal networks - no brains, with nociceptive avoidance behaviour, they make neuronal nets, they have a shared Depression along the DV axis of the larval cnidarian and embryonic vertebrate. |
Shared sentience | Between all cnidaria and bilateria |
Bilaterian brain genes | Pax6 gets coopted in brain of vertebrates - big eyes |
Novelty in bilaterians | Pax6 gets first coopted into the CNS in bilaterians, no sheet formation yet. Pax6 dependent cell types are the serotonergic neurons of the ventral brain of all bilaterian |
Dominance | Vertebrates: dopaminergic or serotonergic system of the hypothalamus detects dominance and status. It can be modulated |
Stag beetle fight | 1 territorial behaviour 2 significant sexual dimorphism 3 ritualized fight behaviour 4 dominance isnt hierarchy 5 hierarchy requires stable social groups 6 dominance can be encoded by pheromones and not expressed |
Species concept | Phenetic species, Ecological species concept, Evolutionary species, Biological species and Recognition Species Concept. |
Phenetic Species | A set of organisms resembling each other and distinct from other sets. |
Ecological Species Concept | Distinct phenetic clusters parasites are a good example |
Evolutionary Species | All individuals that share a common evolutionary history |
Biological Species | Groups of actually or potentially interbreeding natural populations, reproductively isolated from other groups |
Recognition Species Concept | Difficulties in describing sexual isolating mechanisms |
Anagenesis vs Cladogenesis | Anagenesis: descent with modification within a single lineage
Cladogenesis: evolutionary division of lineages, giving a proliferation of species |
Tempos and mode of speciation | Punctuated equilibrium and Phyletic gradualism |
Punctuated equilibrium | The idea that evolution occurs in spurts instead of following the slow, but steady path that Darwin suggested |
Speciation mechanisms | Prezygotic and Postzygotic isolation by Dobzhansky |
Prezygotic isolation | Compatible individuals do not mate. Genetic, ecological and Dobzhansky-Muller theory. |
Postzygotic isolation | Hybrids between members of some groups are less fertile to unfertile. |
Dobzhansky-Muller theory | If speciation involves incompatibility of alleles and genes, then more than 1 genes are involved. |
Modes of speciation | Hybridisation, Instantaneous speciation: single point mutation, chromosomal mutation and polyploidy, Gradual speciation: allopatric, sympatric (driven by co-evolution and lead to character displacement) and parapatric. |
Batesian mimicry | Similarity of edible species to non-edible ones. Tends to be more precise and restricted to one sex. There is a limit to the freq of mimics that can be carried. Crosses between them produce one or the other morph |
Linkage disequilibrium | When he genes do not recombine. It decays over time and chromosomal distance |
Haplotype | A combination of alleles inherited together. Decay depends on the recombination rate (r) which can be 0 to 0.5. a’ = a – r (ad – bc) |
Pin and thrum | 2 morphotypes, increase outbreeding. Pin is recessive to Thrum. G controls the style and female parts and A controls the anthers. |
Dioecy | Has evolved many times. Allows the partitioning of resources, ensures outbreeding. Involves a non recombining region involved in sex determination. |
The mutation theory of the origin of sex | Organisms that have frequent deleterious mutations have a problem. Sex allows the recombination of two degen chromosomes, which can re-establish a good one. |
Upper vs Lower jaw | Premaxilla and Maxilla carried teeth. Only dentary carried teeth. |
2 different forms of bone in skull formation | 1 Dermal bone formation – bone sheet formation directly from mesenchyme
2 Endochondral ossification: Cartilage first and then replaced by bone. |
Head of jawed vertebrates | Chondrocranium: 1st cartilage then replaced by endochondral ossification or bone
Viscerocranium or splanchnocranium: cartilaginous and dermal bone |
Key embryological components | Hindbrain, Branchial arches Mesodermal Limb buds and Mesodermal somites |
Conserved neural crest modules | Discrete cell populations act as developmental modules
They come from specific places and go to specific places
And are instructed in specific ways before migration
Each cell group is one genetic module, and Migrates into one place: A branchial arch. |
Neural Crest | Matching between hindbrain Segment (rhombomere), Neural crest in branchial arch
And its innervation by hindbrain segment – a gnathostome invention! |
Fish Tetrapod transition | A significant paedomorphic event happened: Late adult forms retain features from early larval forms of ancestors
Best indicator: eye/head relationship |
Teeth as developmental modules | 1 Serial repetition, early similarity/odontodes
2. Redeployment of programme from outside to Inside/jaw region in placoderms
3. Differences of teeth – heterodonty/homodonty.
4. Loss of teeth – gradual and complete |
Odontode | Common gnathostome stock –Formation of enameloid. 3 tissues: 1 ectodermal enamel, 2 dentine bone |
Transition | From heterodonty to homodonty. Amniote heterodonty and thecodonty. Primitive condition of Amniotes: teeth along One tooth row. |
Tooth loss | Happened many times independently. Retrograde tooth loss. Lead to new morphologies |