Thus, the gltA1 mutation was necessary for potentiating the evolution of Cit+ because it converted the citT duplication from a prohibitive step downward into a valley in the fitness landscape into a step in an upward mutational route.
As it was, however, their route upward and outward was through the liberation movement.
In an earlier India, that might have been his story's end: there were no second chances then, and there were no other routes upward.
Today, the grown-up children of those Hackney incomers are scrabbling on to the bottom rung of that peculiarly British route to upward mobility, the "housing ladder", in far-off Wanstead and beyond, bringing with them their bicycles, their Guardian values and taste for fancy coffee and organic veg.
To our knowledge, this is the first known natural example of a primary, rather than sporadic, route of upward transmission of a potential pathogen from offspring at an early ontogenetic stage to adult individuals.
Above the Icefall, the route continued up a glacier valley, the Western Cwm, which slopes upward for three miles until it slams into the granite and ice shoulder of Everest, whose summit pyramid looms like a dark blade.
The pulmonary trunk passes diagonally upward to the left across the route of the aorta.
Two routes have been available to castes seeking upward mobility.
Specifically, we show that RPL was designed to mainly support upward traffic, and thus cannot construct reliable multi-hop routes for downward traffic-centric applications.
But early this year the number of train travelers on the route surpassed fliers, and the trajectory is ever upward.
En route there will also be some short, sharp upward moves.
