Sarah Federman a , 1 , Alex Dornburg b , Douglas C. Daly c , Alexander Downie a , George H. Perry d , e , Anne D. Yoder f , Eric J. Sargis g , Alison F. Richard g , Michael J. Donoghue a , Andrea L. Baden h , i , j
11 April 2016
Madagascar is a conservation priority because of its unique and threatened biodiversity. Lemurs, by acting as seed dispersers, are essential to maintaining healthy and diverse forests on the island. However, in the past few thousand years, at least 17 lemur species, many of which were inferred seed dispersers, have gone extinct. We outline the substantial impact that these extinctions have likely had on Malagasy forests by comparing the gape sizes and diets of living and extinct lemurs to identify large-seeded Malagasy plants that appear to be without extant animal dispersers. Additionally, we identify living lemurs that are endangered yet occupy unique and essential dispersal niches. This information can inform conservation initiatives targeting the protection and restoration of these vulnerable ecosystems.
Madagascar’s lemurs display a diverse array of feeding strategies with complex relationships to seed dispersal mechanisms in Malagasy plants. Although these relationships have been explored previously on a case-by-case basis, we present here the first comprehensive analysis of lemuriform feeding, to our knowledge, and its hypothesized effects on seed dispersal and the long-term survival of Malagasy plant lineages. We used a molecular phylogenetic framework to examine the mode and tempo of diet evolution, and to quantify the associated morphological space occupied by Madagascar’s lemurs, both extinct and extant. Using statistical models and morphometric analyses, we demonstrate that the extinction of large-bodied lemurs resulted in a significant reduction in functional morphological space associated with seed dispersal ability. These reductions carry potentially far-reaching consequences for Malagasy ecosystems, and we highlight large-seeded Malagasy plants that appear to be without extant animal dispersers. We also identify living lemurs that are endangered yet occupy unique and essential dispersal niches defined by our morphometric analyses.