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TWO AGING THEORIES. "Evolutionary theories of aging predict the existence of certain genes that provide selective advantage early in life with adverse effect on lifespan later in life (antagonistic pleiotropy theory) or longevity insurance genes (disposable soma theory).” http://www.tandfonline.com/doi/abs/10.4161/cc.28433 View in LinkedIn

INTRON LOSS DOMINATION. "All in all, intron loss clearly dominated the evolution of eukaryotic genes, with episodes of substantial gain linked only with the emergence of some major groups, especially animals, in full agreement with the results of the evolutionary reconstruction for the eukaryotic domain repertoire." http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

"THE DISPOSABLE SOMA THEORY on the evolution of ageing states that longevity requires investments in somatic maintenance that reduce the resources available for reproduction. Experiments in Drosophila melanogaster indicate that trade-offs of this kind exist in non-human species. The findings show that human life histories involve a trade-off between longevity and reproduction." https://lnkd.in/dusZvgm View in LinkedIn

MASSIVE INTRON LOSS. "Remarkably, intron-rich ancestors were reconstructed even for those major groups of eukaryotes that currently consist entirely of intron-poor forms such as the alveolates that apparently evolved via differential, lineage-specific, extensive intron loss." http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

POPULATION SURVIVAL. Disposable soma theory. "That populations survive indefinitely while individuals grow old and die requires that young offspring be produced at the expense of old parents, and this has classically been explained in terms of an immortal germ line passing through a transient and disposable soma, or body." https://lnkd.in/d9ymnPc View in LinkedIn

THE INTRON FACTOR. "The reconstructions consistently indicate that ancestral eukaryotes including the LECA and the founders of each supergroup were intron-rich forms, with intron densities higher than those in the genes of most extant eukaryotes and probably only slightly lower than those in the modern organisms with the most complex gene structures, such as mammals." (LECA = last eukaryotic common ancestor). http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

YEAST CO-OPTED FUNCTION. "Apoptosis rapidly evolved a new, co-opted function in our multicellular yeast with no obvious parallel in the unicellular ancestor. Similarly, the existence of apoptosis-like cellular suicide in the unicellular ancestors of metazoans may be an important preadaptation, facilitating the evolution of complex multicellularity." http://www.pnas.org/content/109/5/1595.full View in LinkedIn

CORROBORATIVE RESULTS. "Remarkably congruent results have been obtained in reconstructions of the gain and loss of introns in eukaryotic genes. In this case, the availability of thousands intron positions provide for the use of powerful ML methods." (ML = maximum likelihood methods). http://onlinelibrary.wiley.com/doi/10.1002/bies.201300037/full View in LinkedIn

YEAST DIVISION OF LABOR. "We also observed the evolution of division of labor within the cluster: most cells remain viable and reproduce, but a minority of cells become apoptotic. Apoptotic cells act as break points within multicellular clusters, allowing snowflake yeast to produce a greater number of propagules from a given number of cells. This is functionally analogous to germ-soma differentiation, where cells specialize into reproductive and nonreproductive tasks. These results demonstrate that multicellular traits readily evolve as a consequence of among-cluster selection." https://lnkd.in/d3qm3Gr View in LinkedIn

EXTRA SPACE. "Until the 20th century, many biologists thought that natural selection favoured old age because it made space for the next generation. If too many people lingered, the group as a whole would suffer. But there was a problem with this logic: the longer individuals live, the more offspring they generally leave. Death might create more room, but it won’t help a species survive." https://lnkd.in/dgftu7G View in LinkedIn