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KEY MECHANISM. “A plethora of processes can create genomic variation in eukaryotes, and we hypothesize that commonly observed chromosomal rearrangements provide a pivotal mechanism to promote adaptation.” https://lnkd.in/eC8eb-V View in LinkedIn

SUCCESS WITHOUT SEXUAL CYCLE. “Thus, these organisms evolved means to generate genomic diversity and compensate for the apparent lack of sexual reproduction.” https://lnkd.in/eC8eb-V View in LinkedIn

PERSISTENT ASEXUAL FUNGUS. “Comparative genomics on Verticillium dahliae, a fungal plant pathogen for which a sexual cycle has never been observed, revealed extensive chromosomal rearrangements that establish lineage-specific genomic regions that are responsible for adaptation to plant hosts and evolution of fungal aggressiveness.” https://lnkd.in/eC8eb-V View in LinkedIn

PROTECTION CAUSES PERSISTENCE. "Lytic viruses were thought to kill the most numerous host (i.e., kill the winner). But persisting viruses/defectives can also protect against viruses, especially in a ubiquitous virosphere. In 1991, Yarmolinsky et al. discovered the addiction modules of P1 phage, in which opposing toxic and protective functions stabilize persistence." https://lnkd.in/dfuhiME View in LinkedIn

PERSISTENT ASEXUAL ROTIFERS. “Bdelloid rotifers are microscopic animals that have persisted for millions of years with an asexual lifestyle, and recent insight in the genome of a bdelloid rotifer confirmed that its genome structure is incompatible with conventional meiosis due to frequent genomic rearrangements.” https://lnkd.in/eC8eb-V View in LinkedIn

GENERATING DIVERSITY. “Chromosomal rearrangements induce a multitude of genomic variations such as duplications, deletions, inversions, and translocations, leading to the gain or loss of genomic material and are observed in both sexual and asexual fungi.” https://lnkd.in/eC8eb-V View in LinkedIn

REDUNDANCY. “The wheat pathogen Mycosphaerella graminicola contains 21 chromosomes of which eight are conditionally dispensable. Particularly, the dispensable chromosomes display a high frequency of chromosomal rearrangements and, in the absence of strong positive selection, have been hypothesized to drive divergence.” https://lnkd.in/eC8eb-V View in LinkedIn

SO ENDS this first part on the evolutionary impact of viruses. They do not fit into the relatively tidy box that Victorian biologists constructed of the world. They defy the idea of species. They frustrate definitions of life. Their form is pure Euclidian geometry. They shimmer at the edge of our definitions of life. They mutate and reproduce at extraordinary rates. And contrary to the old picture, few are pathogenic and many have played an integral role in the evolution of life on this planet. A radical new picture. View in LinkedIn

VIRUSES AND ALL TRANSITIONS. "We can then see that viruses were involved in most all major transitions of host biology in evolution. This will likely seem an overstated or even preposterous position to most readers. How could genetic parasites (viruses) be providing such fundamental capacity for host evolution? And why would they do so?" http://onlinelibrary.wiley.com/doi/10.1111/apm.12485/full View in LinkedIn

ALL PLACENTAL LINEAGES. "Over the years, it has become increasingly evident that endogenized retroviruses (ERVs) have been intimately and deeply involved in the placenta of all mammalian lineages." http://onlinelibrary.wiley.com/doi/10.1111/apm.12485/full View in LinkedIn