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SO ENDS convergent evolution until next weekend. Seemingly improbable, it highlights the importance of selective pressures on an organism finding the best solution; that very different organisms find very similar solutions to selective pressures despite vast structural differences remains one of the fascinating aspects of the topic. It also reveals, surprisingly, that whole phenotypes sometimes may be controlled by only a few genes. View in LinkedIn

MOLECULAR EVOLUTION. "Thus, it appears that resistance to snake venom α-neurotoxin has evolved at least four times among mammals through two distinct biochemical mechanisms operating at the same sites on the same receptor." http://www.sciencedirect.com/science/article/pii/S0041010115000690 View in LinkedIn

TOXIN RESISTANCE. "The muscular nicotinic cholinergic receptor (nAChR), targeted by snake α-neurotoxins, has evolved in some venom-resistant mammals to no longer bind these toxins. Through phylogenetic analysis of mammalian nAChR sequences, we show that honey badgers, hedgehogs, and pigs have independently acquired functionally equivalent amino acid replacements in the toxin-binding site of this receptor." http://www.sciencedirect.com/science/article/pii/S0041010115000690 View in LinkedIn

SCALLOP TYPES. "Our results demonstrate that five of the six life habit types exhibited by scallops have evolved multiple times. We identified 17 repeated transitions between life habit classes within the Pectinidae that were the result of both parallel and convergent evolution." http://bmcevolbiol.biomedcentral.com/articles/10.1186/1471-2148-11-164 View in LinkedIn

CONVERGENCE. "Phytoplasmas are pathogenic bacteria that reprogram plant development such that leaf-like structures instead of floral organs develop. Infected plants are sterile and mainly serve to propagate phytoplasmas and thus have been termed ‘zombie plants’. We suggest that SAP54 underwent convergent sequence evolution to mimic the K-domain of its targets. This enabled it to interact with its MADS-domain protein targets and thereby manipulate plant development to its own benefit." https://lnkd.in/eJF3hwd View in LinkedIn

PARALLEL HIV LINEAGES. ""Some pathogens exhibit striking parallel genomic changes, including multiple HIV lineages that substituted similar mutations conferring antiviral drug resistance and several strains of Escherichia coli that independently acquired similar virulence factors by horizontal transfer." http://www.pnas.org/content/103/24/9107.full View in LinkedIn

SELECTION DRIVEN. "Both parallel evolution and convergent evolution provide strong evidence that the derived similarities resulted from adaptation by natural selection, provided the state-space of possible changes is so large that it is improbable that the observed similarities arose by a purely random process." https://lnkd.in/exArCm7 View in LinkedIn

SEQUENCE CHANGES. "It has been suggested that convergent evolution is characterized by convergent or parallel amino acid substitutions at specific amino acid sites in distant organisms." https://lnkd.in/ePaKzzU View in LinkedIn

RANGE OF EFFECTS. "Common types of epigenetic regulation are DNA methylation and hydroxymethylation, histone modification, chromatin remodeling, and regulation by small and large non-coding RNAs." https://lnkd.in/ewQi_y7 View in LinkedIn

FUNCTION VS SEQUENCE. "The convergent evolution of similar traits in different species could be due to repeated changes at the genetic level or different changes that produce the same phenotypic effect...convergent changes in Hb function generally did not involve parallel substitutions, indicating that repeatability in the evolution of protein function does not require repeatability at the sequence level." (Hb = hemoglobin). https://lnkd.in/eM7WTHC View in LinkedIn