Biodiversity Conservation and Phylogenetic Systematics

366

150

125

100

75

50

25

0

100

50

0

0510

Species Richness

PD

Frequency

Frequency

15 20

0 50 100 150 200

Fig. 3 ( a ) PD of Sarcolaenaceae in the network of protected areas in Madagascar ; ( b ) Frequency
of species richness and PD ( c ) all over Madagascar, and in the cells including protected areas

Discussion

Sarcolaenaceae as a Model Group for Conservation

in Madagascar

As mentioned above, Madagascar ’s biodiversity is among the most distinctive and
highly endemic in the world, and the multiple threats it faces result in it being
among the most threatened as well. There is thus a strong need to evaluate the effec-
tiveness of conservation efforts, in particular the existing network of protected areas
in Madagascar, with respect to their ability to ensure the survival of biodiversity, as
measured not only by species richness but also in terms of phylogenetic diversity. In
particular, PD is assumed to serve as a valuable tool for developing conservation
policies, but to date very few studies have explored it for Madagascar (Sechrest
et al. 2002 ; Magnuson-Ford et al. 2010 ; Isambert et al. 2011 ), only one of which

A. Soulebeau et al.