Limits...
Mammals on the EDGE: conservation priorities based on threat and phylogeny.

Isaac NJ, Turvey ST, Collen B, Waterman C, Baillie JE - PLoS ONE (2007)

Bottom Line: The 100 highest-ranking species represent a high proportion of total mammalian diversity and include many species not usually recognised as conservation priorities.Many species that are both evolutionarily distinct and globally endangered (EDGE species) do not benefit from existing conservation projects or protected areas.The results suggest that global conservation priorities may have to be reassessed in order to prevent a disproportionately large amount of mammalian evolutionary history becoming extinct in the near future.

View Article: PubMed Central - PubMed

Affiliation: Institute of Zoology, Zoological Society of London, London, United Kingdom. nick.isaac@ioz.ac.uk

ABSTRACT
Conservation priority setting based on phylogenetic diversity has frequently been proposed but rarely implemented. Here, we define a simple index that measures the contribution made by different species to phylogenetic diversity and show how the index might contribute towards species-based conservation priorities. We describe procedures to control for missing species, incomplete phylogenetic resolution and uncertainty in node ages that make it possible to apply the method in poorly known clades. We also show that the index is independent of clade size in phylogenies of more than 100 species, indicating that scores from unrelated taxonomic groups are likely to be comparable. Similar scores are returned under two different species concepts, suggesting that the index is robust to taxonomic changes. The approach is applied to a near-complete species-level phylogeny of the Mammalia to generate a global priority list incorporating both phylogenetic diversity and extinction risk. The 100 highest-ranking species represent a high proportion of total mammalian diversity and include many species not usually recognised as conservation priorities. Many species that are both evolutionarily distinct and globally endangered (EDGE species) do not benefit from existing conservation projects or protected areas. The results suggest that global conservation priorities may have to be reassessed in order to prevent a disproportionately large amount of mammalian evolutionary history becoming extinct in the near future.

Show MeSH

Related in: MedlinePlus

Scaling of ED scores with clade size for ten Critically Endangered mammal species. ED scores were calculated at each node between the tips and root for ten species in different orders. Species chosen are: the baiji (Lipotes vexillifer), sumatran rhino (Dicerorhinus sumatrensis), northern hairy-nosed wombat (Lasiorhinus krefftii), persian mole (Talpa streeti), Omiltemi rabbit (Sylvilagus insonus), Przewalski's gazelle (Procapra przewalskii), black-faced lion tamarin (Leontopithecus caissara), Livingstone's flying fox (Pteropus livingstonii), red wolf (Canis rufus) and northern Luzon shrew rat (Crunomys fallax). See Materials and Methods for further details.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC1808424&req=5

pone-0000296-g002: Scaling of ED scores with clade size for ten Critically Endangered mammal species. ED scores were calculated at each node between the tips and root for ten species in different orders. Species chosen are: the baiji (Lipotes vexillifer), sumatran rhino (Dicerorhinus sumatrensis), northern hairy-nosed wombat (Lasiorhinus krefftii), persian mole (Talpa streeti), Omiltemi rabbit (Sylvilagus insonus), Przewalski's gazelle (Procapra przewalskii), black-faced lion tamarin (Leontopithecus caissara), Livingstone's flying fox (Pteropus livingstonii), red wolf (Canis rufus) and northern Luzon shrew rat (Crunomys fallax). See Materials and Methods for further details.

Mentions: We measured ED in clades of different sizes to test whether ED scores from different taxonomic groups are likely to be comparable. We found that most ED is derived from a few branches near the tips (i.e. those shared with few other species) and that virtually no ED is gained in clades above ∼180 species (figure 2). Median ED in clades of 60 species is 88% of the total accumulated using the whole tree (n = 10, figure 2). Moreover, the rank order of ED scores is unaffected by the size of the clade under consideration, except in very small clades and among species with low overall ED (i.e. few of the lines in figure 2 cross one another). These findings suggest that ED scores of different taxonomic groups measured on separate phylogenies (i.e. with no nodes in common) will be comparable, so long as each phylogeny is larger than a threshold size. Based on the scaling observed in figure 2, we suggest a minimum species richness of 100 as a useful rule of thumb to ensure comparability among taxa.


Mammals on the EDGE: conservation priorities based on threat and phylogeny.

Isaac NJ, Turvey ST, Collen B, Waterman C, Baillie JE - PLoS ONE (2007)

Scaling of ED scores with clade size for ten Critically Endangered mammal species. ED scores were calculated at each node between the tips and root for ten species in different orders. Species chosen are: the baiji (Lipotes vexillifer), sumatran rhino (Dicerorhinus sumatrensis), northern hairy-nosed wombat (Lasiorhinus krefftii), persian mole (Talpa streeti), Omiltemi rabbit (Sylvilagus insonus), Przewalski's gazelle (Procapra przewalskii), black-faced lion tamarin (Leontopithecus caissara), Livingstone's flying fox (Pteropus livingstonii), red wolf (Canis rufus) and northern Luzon shrew rat (Crunomys fallax). See Materials and Methods for further details.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC1808424&req=5

pone-0000296-g002: Scaling of ED scores with clade size for ten Critically Endangered mammal species. ED scores were calculated at each node between the tips and root for ten species in different orders. Species chosen are: the baiji (Lipotes vexillifer), sumatran rhino (Dicerorhinus sumatrensis), northern hairy-nosed wombat (Lasiorhinus krefftii), persian mole (Talpa streeti), Omiltemi rabbit (Sylvilagus insonus), Przewalski's gazelle (Procapra przewalskii), black-faced lion tamarin (Leontopithecus caissara), Livingstone's flying fox (Pteropus livingstonii), red wolf (Canis rufus) and northern Luzon shrew rat (Crunomys fallax). See Materials and Methods for further details.
Mentions: We measured ED in clades of different sizes to test whether ED scores from different taxonomic groups are likely to be comparable. We found that most ED is derived from a few branches near the tips (i.e. those shared with few other species) and that virtually no ED is gained in clades above ∼180 species (figure 2). Median ED in clades of 60 species is 88% of the total accumulated using the whole tree (n = 10, figure 2). Moreover, the rank order of ED scores is unaffected by the size of the clade under consideration, except in very small clades and among species with low overall ED (i.e. few of the lines in figure 2 cross one another). These findings suggest that ED scores of different taxonomic groups measured on separate phylogenies (i.e. with no nodes in common) will be comparable, so long as each phylogeny is larger than a threshold size. Based on the scaling observed in figure 2, we suggest a minimum species richness of 100 as a useful rule of thumb to ensure comparability among taxa.

Bottom Line: The 100 highest-ranking species represent a high proportion of total mammalian diversity and include many species not usually recognised as conservation priorities.Many species that are both evolutionarily distinct and globally endangered (EDGE species) do not benefit from existing conservation projects or protected areas.The results suggest that global conservation priorities may have to be reassessed in order to prevent a disproportionately large amount of mammalian evolutionary history becoming extinct in the near future.

View Article: PubMed Central - PubMed

Affiliation: Institute of Zoology, Zoological Society of London, London, United Kingdom. nick.isaac@ioz.ac.uk

ABSTRACT
Conservation priority setting based on phylogenetic diversity has frequently been proposed but rarely implemented. Here, we define a simple index that measures the contribution made by different species to phylogenetic diversity and show how the index might contribute towards species-based conservation priorities. We describe procedures to control for missing species, incomplete phylogenetic resolution and uncertainty in node ages that make it possible to apply the method in poorly known clades. We also show that the index is independent of clade size in phylogenies of more than 100 species, indicating that scores from unrelated taxonomic groups are likely to be comparable. Similar scores are returned under two different species concepts, suggesting that the index is robust to taxonomic changes. The approach is applied to a near-complete species-level phylogeny of the Mammalia to generate a global priority list incorporating both phylogenetic diversity and extinction risk. The 100 highest-ranking species represent a high proportion of total mammalian diversity and include many species not usually recognised as conservation priorities. Many species that are both evolutionarily distinct and globally endangered (EDGE species) do not benefit from existing conservation projects or protected areas. The results suggest that global conservation priorities may have to be reassessed in order to prevent a disproportionately large amount of mammalian evolutionary history becoming extinct in the near future.

Show MeSH
Related in: MedlinePlus