Phylogenetic biome conservatism on a global scale.
How and why organisms are distributed as they are has long intrigued evolutionary biologists. The tendency for species to retain their ancestral ecology has been demonstrated in distributions on local and regional scales, but the extent of ecological conservatism over tens of millions of years and across continents has not been assessed. Here we show that biome stasis at speciation has outweighed biome shifts by a ratio of more than 25:1, by inferring ancestral biomes for an ecologically diverse sample of more than 11,000 plant species from around the Southern Hemisphere. Stasis was also prevalent in transocean colonizations. Availability of a suitable biome could have substantially influenced which lineages establish on more than one landmass, in addition to the influence of the rarity of the dispersal events themselves. Conversely, the taxonomic composition of biomes has probably been strongly influenced by the rarity of species' transitions between biomes. This study has implications for the future because if clades have inherently limited capacity to shift biomes, then their evolutionary potential could be strongly compromised by biome contraction as climate changes.
Crisp
Michael D
MD
School of Botany and Zoology, The Australian National University, Canberra, Australian Capital Territory 0200, Australia. mike.crisp@anu.edu.au
Arroyo
Mary T K
MT
Cook
Lyn G
LG
Gandolfo
Maria A
MA
Jordan
Gregory J
GJ
McGlone
Matt S
MS
Weston
Peter H
PH
Westoby
Mark
M
Wilf
Peter
P
Linder
H Peter
HP
D005075:Biological Evolution; D003247:Conservation of Natural Resources; D003710:Demography; D017753:Ecosystem; D005843:Geography; D010802:Phylogeny; D018521:Plant Physiological Phenomena; D013997:Time Factors