Limits to Speciation Inferred from Times to Secondary Sympatry and Ages of Hybridizing Species along a Latitudinal Gradient

Citations Over TimeTop 10% of 2011 papers

Abstract

Range expansions are critical to renewed bouts of allopatric or parapatric speciation. Limits on range expansions-and, by implication, speciation-include dispersal ability and permeability of geographical barriers. In addition, recently diverged taxa may interfere with each other, preventing mutual expansion of each other's range into sympatry, because reproductive isolation is incomplete and/or ecological competition particularly strong. On the basis of geographical distributions and mitochondrial DNA phylogenetic information for 418 recently diverged species of New World birds, we estimate that secondary sympatry takes on the order of millions of years following population splitting and hence could impose an important limit on the rate of range expansion, thereby limiting further rounds of species formation. Average rates of achievement of sympatry have been faster in the temperate region (we estimate 1.7 million years to sympatry at 60°) than in the tropics (3.2 million years to sympatry at the equator). Evidence from the ages of species with hybrid zones implies that one factor associated with the slowed sympatry in the tropics is the rate of accumulation of reproductive isolation.

Related Papers

• → Natural Selection and the Reinforcement of Mate Recognition(2000)321 cited
• → Divergence in the calling songs between sympatric and allopatric populations of the southern wood cricket Gryllus fultoni (Orthoptera: Gryllidae)(2005)65 cited
• → Character Displacement and Aggression in Two Species ofTerrestrial Salamanders(2002)25 cited
• → Character displacement in Hydrobia(1987)24 cited
• Evaluation of Possible Reproductively Mediated Character Displacement in the Crayfishes, Orconectes rusticus and O. sanbornii(1988)