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Feedback loops link insects to human brains

Ants Swarm Like Brains Think A neuroscientist studies ant colonies to understand feedback in the brain. By Carrie Arnold Illustration by Jonathon Rosen April 23, 2015 Excerpt 1: “The behavior of each individual in the group is set by the rate at which it meets other ants and a set of basic rules. Its behavior alters that of its neighbors, which in turn affects the original ant, in a classic example of feedback. The result is astonishing, complex behavior.” Excerpt…

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Methylation maintains cell type differences

Female Brain Maintained by Methylation Development of female sexual behaviors requires DNA methylation in the preoptic area of the rodent brain. By Anna Azvolinsky | March 30, 2015 Excerpt: “…programmed during brain development, but how exactly this occurs is not clear. In the preoptic area (POA) of the brain…” My comment: See the section on molecular epigenetics in our 1996 Hormones and Behavior review: From Fertilization to Adult Sexual Behavior Excerpt: “Small intranuclear proteins also participate in generating alternative splicing…

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Quantum correlations/pseudoscience

A quantum advantage for inferring causal structure Preprint excerpt: “The causal inference schemes described here promise extensive applications in experiments exhibiting quantum eff ects. For instance, they can provide a test of whether the dynamics of a given open quantum system is Markovian or not [17{24]. This is because in a non-Markovian evolution, the environment acts as a common cause between the dynamical system at one time and the same system at a later time. Our inference schemes may also help…

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From Hydra to humans vs a Lakatosian research program

Imre Lakatos Excerpt: “A Lakatosian research programme[8] is based on a hard core of theoretical assumptions that cannot be abandoned or altered without abandoning the programme altogether. More modest and specific theories that are formulated in order to explain evidence that threatens the ‘hard core’ are termed auxiliary hypotheses. Auxiliary hypotheses are considered expendable by the adherents of the research programme—they may be altered or abandoned as empirical discoveries require in order to ‘protect’ the ‘hard core’. Whereas Popper was…

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Ecological adaptations reported as evolution in insects and mammals

Evolution of mosquito preference for humans linked to an odorant receptor Excerpt: “Our results also provide insight into the molecular basis of behavioural evolution.” See their diagram in Extended Data Figure 3: Amino acid differences of major Or4 protein alleles. Excerpt: Dots represent amino acid differences with respect to the genome reference, not an inferred ancestor. Reported as: Study suggests how mosquitoes evolved an attraction to human scent Excerpt: The switch from preferring animals to humans involves a variety of…

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Insect homology and diversity attributed to mutations

Ancient homology underlies adaptive mimetic diversity across butterflies Excerpt: “Surprisingly, our results suggest that modulation of this conserved developmental gene has occurred in tandem between these two deeply divergent butterfly lineages, implying an unexpected and remarkable level of predictability in the evolutionary process.” Reported as: A single evolutionary road may lead to Rome Excerpt: “Copying errors and genomic viruses directly lead to the wing patterns of these beautiful butterflies,” Gallant said. “It’s these accidents that allow the evolutionary process to…

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Drunks and Monkeys: Pseudoscientific nonsense

Drunks and Monkeys Understanding our primate ancestors’ relationship with alcohol can inform its use by modern humans. By Robert Dudley | June 1, 2014 Excerpt: “…if the right kinds of bacteria are also present, fermentation will stabilize certain foodstuffs (think cheese, yogurt, sauerkraut, and kimchi, for example).” My comment:  Epigenetic changes induced by ethanol in astrocytes link histone acetylation, DNA methylation, and non-coding microRNAs in the developing and adult brain from frugivory to the nutrient-dependent de novo creation of olfactory receptor genes in bats. The…

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Behavior is receptor-mediated

Mechanism explains complex brain wiring Excerpt: “How neurons are created and integrate with each other is one of biology’s greatest riddles.” My comment: The biology of behavior is receptor-mediated. If you can convince people it is not receptor-mediated, you can probably convince them that the different morphological and behavioral phenotypes of species from microbes to man somehow evolved via mutations and natural selection rather than via RNA-mediated events. However, without the nutrient-dependent pheromone-controlled de novo creation of olfactory receptor genes,…

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Ecologically linked adapted ants and brains

Ants Swarm Like Brains Think A neuroscientist studies ant colonies to understand feedback in the brain. By Carrie Arnold April 24, 2014 Excerpt: “The behavior of each individual in the group is set by the rate at which it meets other ants and a set of basic rules. Its behavior alters that of its neighbors, which in turn affects the original ant, in a classic example of feedback. The result is astonishing, complex behavior.” My comment: The molecular mechanisms of…

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Nutrient-dependent pheromone-controlled stickleback evolution

Sexual imprinting on ecologically divergent traits leads to sexual isolation in sticklebacks Excerpt: “Odour differences may be owing to pleiotropic effects of adaptive differences in diet [18], habitat [12] and major histocompatibility complex (MHC) alleles selected by parasite differences [19,20].” Excerpt: “…imprinting has turned odour and nuptial coloration into magic traits.” My comment: In my model, natural odour production in vertebrates is not a magic trait. It results from the role of food odours in nutrient-dependent RNA-mediated ecological niche construction.…

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