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UNFINISHED TREND. “Today, the number of house sparrows in North America is only some 25 million, and the trend continues downward.” https://link.springer.com/chapter/10.1007/978-3-319-55396-2_5 View in LinkedIn

US SPARROW COLLAPSE. “After its introduction in the 1850s, the house sparrow quickly spread across North America, and 40 years later, it had colonized large parts of the continent. At its peak, the number could have touched half a billion. After that, the house sparrow population shrank in stages with periodic rapid decreases. In between, the numbers stabilized, before the decline continued. Lately, subpopulations, especially in the big cities, have all but collapsed.” https://lnkd.in/dGi32hq View in LinkedIn

EUROPEAN SPARROW COLLAPSE. “Dutch house sparrow (Passer domesticus) densities dropped by nearly 50% since the early 1980s, and similar collapses in population sizes have been reported across Europe.” https://lnkd.in/dyehfe7 View in LinkedIn

SPARROW MICROBIOTA. “We found urbanisation to be associated to lower microbiota species diversity, modifications in taxonomic composition and community structure, and changes in functional composition. Our results hence shed light on a hitherto little considered perspective, i.e. that the negative effects of urbanisation on city-dwelling organisms may extend to their microbiomes, causing potential dysbioses.” https://lnkd.in/dyfjm-b View in LinkedIn

HIGHLY SOCIAL BIRDS. “Reduction of colony size below some critical threshold may impair breeding behaviour to the extent that success declines, perhaps ultimately resulting in the disappearance of the colony...and increased dispersion of the colonies.” https://www.britishbirds.co.uk/wp-content/uploads/article_files/V96/V96_N09/V96_N09_P439_446_A004.pdf View in LinkedIn

DEFENSES. “Species that are well protected from predators – for example, those that have a shell, can fly, or are poisonous – tend to live longer than related, less well-protected species.” http://www.nature.com/scitable/knowledge/library/the-evolution-of-aging-23651151 View in LinkedIn

THE BALANCE. “The evolution of lifespan can be viewed as a balance between selection for increased reproductive success and the factors that increase the intrinsic age-dependent components of mortality.” http://www.nature.com/scitable/knowledge/library/the-evolution-of-aging-23651151 View in LinkedIn

THE EQUATION. “These lifespan promoting effects of selection are balanced by those that tend to increase adult mortality relative to juvenile mortality. Consequently, if extrinsic, environmentally imposed adult mortality is high, selection becomes weak, thereby allowing the evolution of higher levels of intrinsic mortality (i.e., aging).” http://www.nature.com/scitable/knowledge/library/the-evolution-of-aging-23651151 View in LinkedIn

LIFESPAN AND BREEDING. “A longer lifespan normally implies increased reproductive success, and factors such as low adult mortality (permitting more reproductive events per lifetime), high juvenile mortality (making it necessary for adults to reproductively compensate for such loss), and high variation in juvenile mortality from one bout of reproduction to the next (increasing uncertainty in reproductive success and requiring reproductive compensation as well) therefore all tend to lengthen reproductive lifespan.” http://www.nature.com/scitable/knowledge/library/the-evolution-of-aging-23651151 View in LinkedIn

REPLICOMETER. “Telomeric shortening appears to be the replicometer that determines the number of times that a normal cell is able to divide. Once a threshold number of telomeric (TTAGGG) repeats is reached, downstream events presumably are triggered that signal the cessation of DNA replication. Wright and Shay have offered an alternative explanation of how telomere shortening acts as a replicometer.” https://lnkd.in/esfPTAR View in LinkedIn