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SEXUAL DRIVERS OF VARIATION. “Before genetic information is transferred to the progeny, meiotic recombination generates novel combinations of existing alleles. It is therefore not surprising that meiotic recombination is considered an important driver for rapid adaptation of pathogens to their hosts.” https://lnkd.in/eC8eb-V View in LinkedIn

"SELFISH ELEMENTS make key contributions to evolutionary transitions at least at two levels. First, the parasite–host arms race leads to increased organizational complexity of biological systems, i.e. serving as a catalyst of evolutionary transitions. Second, viruses and mobile elements contribute specific genes that play major roles in the emergence of coherent wholes at a new level of complexity." https://lnkd.in/daxmUKR View in LinkedIn

TRANSITIONS DRIVEN BY VIRUSES. "I present evidence that, at least up to and including the origin of multicellularity, evolutionary transitions are driven by the coevolution of hosts with these genetic parasites along with sharing of ‘public goods’." https://lnkd.in/daxmUKR View in LinkedIn

EVOLUTIONARY TRANSITIONS. "The history of life is punctuated by evolutionary transitions which engender emergence of new levels of biological organization that involves selection acting at increasingly complex ensembles of biological entities. Major evolutionary transitions include the origin of prokaryotic and then eukaryotic cells, multicellular organisms and eusocial animals." https://lnkd.in/daxmUKR View in LinkedIn

UBIQUITOUS VIRAL PARASITES. "All or nearly all cellular life forms are hosts to diverse selfish genetic elements with various levels of autonomy including plasmids, transposons and viruses." https://lnkd.in/daxmUKR View in LinkedIn

PROFESSOR LLUIS P VILLARREAL, an extraordinary thinker and researcher. "For the last 15 years, I have focused my study on the general role of virus evolution on Life. In the last decade metagenomic assessments have led us to realize that viruses are the dominate biological entities of the biosphere and are the most numerous, diverse and dynamic genetic agents on Earth. I am now tracing how viruses have contributed to host group survival from bacteria to human social evolution." https://lnkd.in/enQH9Fn View in LinkedIn

FRAGMENT FROM NATURE focuses for this and next weekend on the work of Professor Lluis Villarreal, who has proposed that viruses have played an intimate role in human evolution, and all major evolutionary transitions. He has been an outspoken and sometimes controversial voice for this biological dark matter at a time when most biologists dismiss viruses as oddball curiosities that are more chemical than living. They have left their traces in our genomes, have fashioned some of the great cycles on this planet, defy species limits, and outnumber other creatures. Enjoy this glimpse into biological dark matter that is mostly left in the biological rubbish bin. View in LinkedIn

GENE CHUNKING. “In addition to the transfer of single genes, also the transfer of entire chromosomes has been documented in pathogenic fungi. This typically involves conditionally dispensable chromosomes that are not required for growth, but confer an advantage when colonizing particular ecological niches.” https://lnkd.in/eC8eb-V View in LinkedIn

CROSS-BARRIER GENE SHARING. “The exchange of genes over species barriers – referred to as horizontal or lateral gene transfer – can play an important role in genome evolution.” https://lnkd.in/eC8eb-V View in LinkedIn

VARIOUS MECHANISMS. “Several mechanisms can alter the genetic material of eukaryotic species: A: DNA point mutations (stars) can alter single (or few) nucleotides. B: Genetic material can be transferred from a donor lineage over species barriers (dashed line) into the genome of an acceptor lineage. This can either be limited to single genes (horizontal gene transfer) or comprise entire chromosomes (horizontal chromosome transfer). C: Inter- or intra-chromosomal rearrangements can lead to a variety of genomic changes. Double-strand breaks are indicated by red arrows and dashed lines.” https://lnkd.in/eC8eb-V View in LinkedIn