Past projects

How did the Cretaceous-Palaeogene mass extinction influence reef evolution?
The origins and assembly of the reef fish fauna is poorly described. A patchy fossil record suggests that the major colonization of reef habitats must have occurred in the Late Cretaceous and early Palaeogene, with the earliest known modern fossil coral reef fish assemblage dated to 50 Ma. Using a phylogenetic approach, I analysed the early evolutionary dynamics of modern reef fishes, finding that reef lineages successively colonized reef habitats throughout the Late Cretaceous and early Palaeogene. Two waves of invasion were accompanied by increasing morphological convergence: one in the Late Cretaceous from 90 to 72 Ma and the other immediately following the end-Cretaceous mass extinction. The surge in reef invasions after the Cretaceous–Palaeogene (K-Pg) boundary continued for 10 Myr, after which the pace of transitions to reef habitats slowed. Combined, these patterns match a classic niche-filling scenario: early transitions to reefs were made rapidly by morphologically distinct lineages and were fol- lowed by a decrease in the rate of invasions and eventual saturation of morphospace. This study is one of a few that use phylogenies to investigate explicit patterns of biodiversity through time rather than between lineages.
Price, S. A., Schmitz, L., Oufiero, C. E., Eytan, R.I., Dornburg, A.,  Smith, W.L., Friedman, M., Near, T.J., Wainwright, P.C. (2014) Two waves of colonization straddling the K-Pg boundary formed the modern reef fish fauna. Proceedings of the Royal Society of London, B. 281(1783): 20140321.
Do reef habitats influence the rate of ecomorphological evolution?
Coral reefs are one of the most diverse ecosystems on earth and yet we know little about the evolutionary and ecological mechanisms that generate or maintain such spectacular diversity. Using stochastic character-mapping to sample the history of habitat shifts in labrids and haemulids I have shown that evolutionary-informed rates of functional morphological evolution are approximately twice as fast in complex coral reef environments. In addition I found that coral reef species occupy more trophic morphospace than non-reef species. These results suggest that the preservation of coral reefs is necessary, not only to safeguard current biological diversity but also to conserve the underlying mechanisms that can produce functional diversity in the future
Price, S. A., Tavera, J. J., Near. T. J. & Wainwright, P.C. (2013) Elevated rates of morphological and functional diversification in reef-dwelling haemulid fishes. Evolution 67(2), 417-428.
Price, S.A., Holzman, R. & Wainwright, P.C. (2011) Coral reefs promote the evolution of morphological diversity and ecological novelty in fishes. Ecology Letters 14(5), 462-469.
Do the functional innovations in the pharyngeal jaws of parrotfishes influence the rate of oral jaw evolution?
The association between diversification and evolutionary innovations has been well documented and tested in studies of taxonomic richness but the impact that such innovations have on the diversity of form and function is less well understood.  To address this question we investigated the impact of two design breakthroughs within the jaws of parrotfishes, the novel intramandibular joint and the modified pharyngeal apparatus.  We quantified morphological diversity within six functionally important oral jaw traits using the Brownian motion rate of evolution to correct for phylogenetic and time-related biases and compared these rates across clades that did and did-not possess the intramandibular joint and the parrotfish pharyngeal jaw. We found that no change in morphological diversity was associated with the pharyngeal jaw modification alone but rates of oral jaw diversification were up to 8x faster in parrotfish species that possessed both innovation.
Price, S.A., Wainwright, P.C., Bellwood, D.R, Kazancioglu, E., Collar, D.C. & Near, T.J. (2010) Functional innovations and morphological diversification in parrotfishes. Evolution, 64(10), 3057-3068.
Are whales an dolphins an adaptive radiation?
Modern whales have often been described as an adaptive radiation spurred either by key innovations or ecological opportunity following the demise of archaic whales. However, recent analyses of diversification rate shifts using molecular phylogenies have found no evidence of increased speciation rates during the early evolution of living whales. We repeated these analyses building a time-calibrated molecular phylogeny and in addition looked for the pattern of early ecological diversification which is also expected to accompany adaptive radiations. We used a data mining approach to gather a data from the literature on body length and diet and analysed it using disparity-through-time plot shown to the left and fitting various models of evolution.  We that show cetacean lineages partitioned size niches early in the evolutionary history of modern whales and that changes in size are consistent with shifts in dietary strategy. We conclude that the signature of adaptive radiations may be retained within morphological traits even after the signature of an early burst of diversification has been erased from the structure of the phylogeny. This study was in collaboration with Graham Slater, Francesco Santini & Mike Alfaro.
Slater, G.J.*, Price, S.A.*, Santini, F. & Alfaro, M.E. (2010) Diversity versus disparity and the radiation of modern cetaceans. Proceedings of the Royal Society of London, B. 277, 3097-3104.
How does human hunting influence the biological factors associated with extinction vulnerability?
Many biological characteristics have been show to correlate with current extinction risk across a variety of mammalian orders but does the type of threatening process affect which traits predispose them to extinction? We used a multivariate model to assess which biological, anthropogenic and environmental factors influence variation in current extinction risk in even-toed hoofed mammals (pigs, deer, cows, giraffes, antelope etc.). Species that experienced unregulated hunting live in significantly less economically developed areas than those that are not hunted and hunted species were more susceptible to extinction if they have slower reproductive rates. In contrast, risk in non-hunted artiodactyls was unrelated to reproductive rate and more closely associated with the economic development of the region in which they live.

This study is the basis for an online module for undergraduate students I have developed in conjunction with the Dryad data repository. It aims to teach students about extinction as an evolutionary process and a conservation concern by getting the students to analyze our data.
Price, S.A. & Gittleman, J.L. (2007)  Hunting to extinction: biology and regional economy influence artiodactyl extinction risk and the impact of hunting. Proceedings of the Royal Society of Science B, 274, 1845-1851.