Given the complexity of mechanisms driving body size variation, the adaptive nature of size changes needs to be evaluated for each specific case, if we are to understand their evolutionary consequences on population dynamics and persistence.
They're driving American-size cars on American-size roads to American-size homes and eating American-size Big Macs".
The researchers say this is the first example of social competition driving genitalia size in vertebrates.
Also, to better understand the role of movement in driving population size, we contrast our findings with a null model of no migration, in which we force the wildebeest to become sedentary and confined to restricted home ranges, with no movement even within the two pieces separated by the road.
As a corollary, extant patterns of duplicability need not be representative of the forces driving family size evolution in the longer term.
The relative rates of small insertions and deletions and the degree to which these mutations are favored or not by natural selection appear to be the main forces driving genome size evolution (Petrov et al. 2000; Lynch 2007).
This study focused on annotated transposase ORFs in Frankia sp. and the identification of fragmentary IS elements present in three strains of Frankia sp. Their positioning and diversity suggest roles in driving genome size and strain differences that may have contributed to the adaptation of different Frankia lineages to their hosts and soils.
But now we know a lot about beaks - beaks are bony structures, they're induced by neural crest cells that migrate into the head at various places, and one of the main things driving beak size is signaling through the BMP2/4 bone morphogenetic proteins.
Keep different sized combs on hand in case you are driving different sized nails.
They aim to end dropout rates in primary and lower-secondary schools and improve the quality of learning by recruiting more teachers and driving class sizes down.
