Month: September 2022

POLLINATOR EXAMPLES. "Permanent reciprocal selective pressure between pairs of coevolving species can lead to a coevolutionary race and rapid evolutionary change. This is exemplified by spurred flowers and long-tongued flower-visitors." A lovely review. https://lnkd.in/dyf9mxs View in LinkedIn

TRANSITIONS DUE TO COEVOLUTION. "Many major events in the history of life may be attributed to reciprocal coevolutionary change, including the origin of the eukaryotic cell, the origin of plants, the evolution of coral reefs, and the formation of lichens, mycorrhizae, and rhizobia." https://lnkd.in/d3gZgG7 View in LinkedIn

MYXOMATOSIS EXAMPLE. "The classic example is the European rabbit–myxoma virus system in which, after the virus was introduced into a naïve rabbit population, phenotypic changes were observed in both pathogen and host components of virulence. The rapid, initial attenuation of the virus presumably represents adaptation to a novel host. But subsequent slower increases in both virus pathogenicity and the ability of the host to survive infection are consistent with co-evolution." https://lnkd.in/d3-W8NW View in LinkedIn

GENETIC COMPATIBILITY. "Theoretical studies of co-evolution date back over 40 years; examples include ‘gene-for-gene’, ‘matching allele’ and ‘matching genotype’ models. The key feature of these models is that the outcome of the host–pathogen interaction depends on the combination of host and pathogen genotypes involved." https://lnkd.in/d3-W8NW View in LinkedIn

COEVOLUTION VARIABLES: "whether the genome is haploid or diploid; the number of alleles involved and whether there is pleiotropy (especially fitness costs independent of the host–pathogen interaction); dominance relationships between alleles; the number of loci involved and whether there is epistasis; whether reproduction is sexual or asexual; whether mating is random or assortative; and the relative generation times of host and pathogen and whether generations are discrete or continuous." https://lnkd.in/d3-W8NW View in LinkedIn

SO ENDS this first of two weekends on coevolution. It seems intuitive that two interdependent creatures could affect each others evolutionary trajectory. Thus the continuity of the germplasm into the future — that driver of life — is not simply affected by successful mating and gene reshuffling, but by what type of company you keep, wittingly or not. This includes the microbiome of multiple creatures in and on your body. This is an exemplar of Darwin’s tangled bank seen through the lens of time, dynamic and active. View in LinkedIn

POLY-FUNCTIONAL DNA. "Multiple Overlapping Genetic Codes Profoundly Reduce the Probability of Beneficial Mutation. There is growing evidence that much of the DNA in higher genomes is poly-functional, with the same nucleotide contributing to more than one type of code. Such poly-functional DNA should logically be multiply-constrained in terms of the probability of sequence improvement via random mutation." https://lnkd.in/d2ZFuRp View in LinkedIn

RUDIMENTARY CODE MEMORY. "Computer-simulated life forms which reproduce themselves inside their electronic world have evolved to produce basic intelligence. After thousands more generations, the Avidians had evolved something more impressive: a rudimentary memory. The environment sets up selective pressures so organisms are forced to come up with some kind of memory use - which is in fact what they do." https://lnkd.in/dQNwFn2 View in LinkedIn

EMERGENT TRAITS. "In the past, the approach has been to start with high-level intelligence and reproduce that in a computer. This is the opposite. We're showing how complex traits like memory can be built from the bottom up, from things that are really very simple." https://lnkd.in/dQNwFn2 View in LinkedIn

CHEMICAL VS DIGITAL CODE. "Striking architectural similarities between higher genomes and computer executable code." https://lnkd.in/de9z-Pn View in LinkedIn