Rare combination of genetic changes increases the virulence of canine distemper virus

Study explains how CDV killed lions, spotted hyenas in the Serengeti 

Date: December 8, 2016
Source: Forschungsverbund Berlin e.V. (FVB)

Summary:The long-running debate about why just one of several canine distemper virus (CDV) outbreaks in the Serengeti in Tanzania during the past 25 years was fatal for lions and spotted hyenas has been resolved. An international team of scientists conducted genetic analyses of CDV strains obtained from a range of carnivores between 1993 and 2012 and discovered that lethal CDV infections in lions and hyenas during the 1993/1994 epidemic was caused by a rare and genetically distinct CDV strain with three rare mutations not present in any other Serengeti strain isolated from domestic dogs or wild canids. Two of these rare mutations were found to increase the ability of CDV to invade lion cells.  

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Rare Glimpse Into the Origin of Species

ScienceDaily (July 10, 2012) — A new species of monkey flower, created by the union of two foreign plant species, has been discovered on the bank of a stream in Scotland. Genetic changes in this attractive yellow-flowered hybrid have allowed it to overcome infertility and made it a rare example of a brand new species that has originated in the wild in the last 150 years. Thousands of wild species and some crops are thought to have originated in this way, yet only a handful of examples exist where this type of species formation has occurred in recent history.

The ancestors of the new plant were brought from the Americas as botanical curiosities in the 1800s and were quickly adopted by Victorian gardeners. Soon after their arrival, they escaped the confines of British gardens and can now be found growing in the wild, along the banks of rivers and streams. Reproduction between these species produces hybrids that are now widespread in Britain. Yet, genetic differences between the two parents mean that the hybrids are infertile and cannot go beyond the first generation.

Dr Mario Vallejo-Marin, a plant evolutionary biologist at the University of Stirling, has documented the first examples of hybrid monkey flowers that have overcome these genetic barriers and show fully restored fertility. This fertile hybrid derived from 'immigrant' parents represents a new species, native to Scotland. Dr Vallejo-Marin has chosen to name this species Mimulus peregrinus, which translates as 'the wanderer'. The species is described in the open access journal PhytoKeys.

Continued: http://www.sciencedaily.com/releases/2012/07/120710120231.htm