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SOURCE. “Here, we aim to address three outstanding questions regarding Y. pestis history. First, we investigate the possibility of disease entry via multiple pulses during the Black Death by comparing the genotype of a strain from the pandemic’s early phase to those circulating in other areas later in the pandemic.” https://lnkd.in/g9Pgxuv View in LinkedIn

PLAGUE PERSISTENCE. “After the Black Death, plague continued to strike Europe for another four centuries through subsequent outbreaks that ceased at the end of the 18th century. The reasons for its sudden disappearance in Europe are unknown. Sylvatic plague foci have a nearly worldwide presence today, but are absent in Europe.” https://lnkd.in/g9Pgxuv View in LinkedIn

FROM EUROPE TO CHINA. “Ancient Y. pestis genomes obtained from medieval victims have indicated the presence of a radiation event immediately preceding the Black Death that gave rise to most of the strain diversity circulating in the world today. Based on the relationship of ancient European and modern genomes, it was recently suggested that a wave of plague might have traveled from Europe toward Asia after the Black Death, eventually settling in China and later giving rise to the third pandemic.” https://lnkd.in/g9Pgxuv View in LinkedIn

HISTORICAL RECORD. “To our knowledge, bubonic plague, and presumably also the pneumonic and septicemic forms, have been the likely culprit of three major pandemics, namely the Plague of Justinian (Eastern Roman Empire, 6th and 8th centuries AD), the second-wave plague pandemic (Europe, mid-14th century Black Death until the mid-18th century AD), and the third plague pandemic that started during the late 19th century in China. In recent years, however, ancient DNA (aDNA) has confirmed a Y. pestis involvement in both historical pandemics.” https://lnkd.in/g9Pgxuv View in LinkedIn

GENETIC LINEAGE. “Yersinia pestis evolved from the closely related zoonotic enterobacterium Y. pseudotuberculosis to become one of the most virulent pathogens known to humans. Its recent identification in ancient human material from Altai, Siberia suggests it caused human infections as early as 5,000 years ago, though its ability for flea-borne transmission leading to bubonic disease might have been absent in these older, divergent lineages.” https://lnkd.in/g9Pgxuv View in LinkedIn

AT LEAST THREE BLACK DEATHS. “Yersinia pestis has caused at least three human plague pandemics. The second (Black Death, 14–17th centuries) and third (19–20th centuries) have been genetically characterised, but there is only a limited understanding of the first pandemic, the Plague of Justinian (6–8th centuries).” https://lnkd.in/gY5rX65 View in LinkedIn

FIRST ANGIOSPERM. "Recent sequencing analyses suggest strongly that Amborella trichopoda, an evergreen dioecious shrub endemic to New Caledonia, is the first branch of angiosperm evolution." https://lnkd.in/gb3zS32 View in LinkedIn

FAMILY TREE RECONSTRUCTIONS. "Many attempts have been made, using morphological and molecular systematics, to reconstruct the early evolutionary history of the 250 000 or so species of flowering plants." https://lnkd.in/gb3zS32 View in LinkedIn

"DISTYLY has probably arisen to promote pollen dispersal (and therefore outcrossing) and is often associated with self incompatibility. Specialization of one type for maleness and the other for femaleness may progress to full dioecy." https://lnkd.in/gb3zS32 View in LinkedIn

“HETEROSTYLY is a unique form of polymorphism and herkogamy in flowers. In a heterostylous species, two or three morphological types of flowers, termed "morphs", exist in the population. On each individual plant, all flowers share the same morph. The flower morphs differ in the lengths of the pistil and stamens, and these traits are not continuous.“ https://lnkd.in/dBgeGam View in LinkedIn