Year: 2022

ACCELERATION OF EFFICIENCY. "Evolution has bootstrapped its own process, creating the conditions that lead to more efficient evolution. Some biologists find this surprising, but it has undoubtedly occurred. Among the traits that lead to more efficient evolution is aging." http://joshmitteldorf.scienceblog.com/2013/07/22/evolution-of-evolution-and-evolution-of-death/ View in LinkedIn

"AGING evolved first to promote demographic stability." http://joshmitteldorf.scienceblog.com/2013/07/22/evolution-of-evolution-and-evolution-of-death/ View in LinkedIn

FRAGMENT FROM NATURE concludes this weekend on the contemplation of biological complexification during evolution, with a focus on reductive evolution in genomes. It is generally thought that evolution always leads to greater complexity. But new evidence suggests that bursts of genetic complexification tend to be followed by long periods of genetic streamlining and loss of genes. This is not just true of parasites and symbiotic creatures, but surprisingly, also of eukaryotes. View in LinkedIn

EVIDENCE-BASED. "Genomic complexity is far easier to quantify than phenotypic complexity (even if the latter is easier to recognize intuitively). Indeed, the remarkable progress of genome sequencing, combined with the development of computational methods for advanced comparative genomics, provides for increasingly reliable reconstruction of ancestral genomes which transforms the study of the evolution of complexity from being a speculative exercise to becoming an evidence-based research direction." http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

EXTREME GENOMICS. "Deep genome reduction, with the smallest sequenced genome of only 2.9 Mb, is also observed in Microsporidia, the eukaryotic intracellular parasites that appear to be highly derived fungi. The most extreme genome reduction among eukaryotes is observed in nucleomorphs which are remnants of algal endosymbionts present in cryptophytes and chlorarachniophytes and retain only a few hundred genes." http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

OUTSOURCING LIFESTYLES. "Beyond parasites and symbionts, reductive evolution was observed in several groups of organisms that evolved a commensal life style." http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

STREAMLINING EXEMPLAR. "One of the best-characterized cases involves the Lactobacillales, a group of Gram-positive bacteria that is extremely common in a variety of animal- and plant-associated habitats. A maximum parsimony reconstruction revealed substantial gene loss, from ∼3,000 genes in the common ancestor of Bacilli to ∼1,300–1,800 genes in various Lactobacilli species." http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

NET BALANCE. "The genes apparently have been lost in a stepwise manner, with substantial loss associated with each internal branch of the tree and most but not all of the individual species. These losses were only to a small extent offset by inferred gain of new genes." http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

TWO METHODS. "Genome reduction apparently occurs in two distinct and distinguishable manners, i.e. either via a neutral ratchet of genetic material loss or by adaptive genome streamlining." http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

CONSTRAINTS ON REDUCTIONS. "Certainly, the evolution of the genomes of parasites, symbionts and commensals is not a one-way path of reduction. On the contrary, the reduction ratchet is constrained by the advantages of retaining certain metabolic pathways that complement the host metabolism." http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn