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Menticol online dating

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The distributions of the species are also relatively well documented and encompass a wide geographic range across the cool temperate and cold regions of the Holarctic and beyond, including Eurasia, North America, Africa north of the Sahara, and much of South America (Williams, 1998).Although distributional patterns of extant bumble bees suggest possible scenarios for historical biogeography and fossil evidence provides approximate dates for these events, estimation of the ancestral biogeographic distributions of (e.g., Plowright and Stephen, 1973; Ito, 1985; Williams, 1985, 1994; Pedersen, 2002; Cameron and Williams, 2003; Kawakita et al., 2004; Hines et al., 2006).

Divergence times, historical biogeography, and diversification statistics were estimated using the phylogeny and data set published in Cameron et al. This data set contains 218 taxa with unique names, including representatives of all 38 subgenera (Williams, 1998).Dispersal-vicariance analysis (DIVA) predicted an Old World ancestor, with early diversification events largely restricted to the eastern Old World.The numerous intercontinental dispersal events occurred mostly in the direction of Old World to New World and North America to South America.A simplified subgeneric system for the bumble bees upon the 38 subgenera employed here and in Cameron et al. The sequence data include ∼ 3745 amplified nucleotides, including both intron and exon regions from five genes: mitochondrial 16S r DNA, elongation factor-1α F2 copy (EF-1α), long-wavelength rhodopsin (opsin), arginine kinase (Arg K), and phosphoenolpyruvate carboxykinase (PEPCK).Missing species are mostly from the mountains of Asia and fall rather evenly across the subgenera (Cameron et al., 2007), with the exception of (5 of 12 species missing).The only reliable (Cockerell, 1931) from the Miocene Latah Formation in Washington, USA (∼ 12.1 to 21.3 Ma; Gray and Kittleman, 1967).

As species-level phylogenies become increasingly resolved and complete, they provide opportunities to more confidently explore the tempo of diversification (Barraclough and Nee, 2001).

) are a cold-adapted, largely alpine group that can elucidate patterns of Holarctic historical biogeography, particularly in comparison to the alpine plants with which they likely coevolved.

A recently published molecular phylogeny of bumble bees provides uniquely comprehensive species sampling for exploring historical patterns of distribution and diversification.

Early movements from the Palearctic into the Nearctic most likely took place after 20 Ma and may have coincided with a period of Miocene cooling that gave rise to taiga habitat across Beringia.

Subsequent dispersal between these regions is estimated to have occurred among boreal and tundra-adapted species mostly in the last 5 million years.

Accordingly, using paleontological and morphological evidence, Grimaldi and Engel (2005) estimated an 80-to 90-Ma corbiculate bee diversification.