The modern marine megafauna is known to play important ecological roles and includes many charismatic species that have drawn the attention of both the scientific community and the public. However, the extinct marine megafauna has never been assessed as a whole, nor has it been defined in deep time. Here, we review the literature to define and list the species that constitute the extinct marine megafauna, and to explore biological and ecological patterns throughout the Phanerozoic. We propose a size cut-off of 1 m of length to define the extinct marine megafauna. Based on this definition, we list 706 taxa belonging to eight main groups. We found that the extinct marine megafauna was conspicuous over the Phanerozoic and ubiquitous across all geological eras and periods, with the Mesozoic, especially the Cretaceous, having the greatest number of taxa. Marine reptiles include the largest size recorded (21 m; Shonisaurus sikanniensis) and contain the highest number of extinct marine megafaunal taxa. This contrasts with today’s assemblage, where marine animals achieve sizes of >30 m. The extinct marine megafaunal taxa were found to be well-represented in the Paleobiology Database, but not better sampled than their smaller counterparts. Among the extinct marine megafauna, there appears to be an overall increase in body size through time. Most extinct megafaunal taxa were inferred to be macropredators preferentially living in coastal environments. Across the Phanerozoic, megafaunal species had similar extinction risks as smaller species, in stark contrast to modern oceans where the large species are most affected by human perturbations. Our work represents a first step towards a better understanding of the marine megafauna that lived in the geological past. However, more work is required to expand our list of taxa and their traits so that we can obtain a more complete picture of their ecology and evolution.

There is growing evidence to suggest that there is an increase in species extinction occurring globally. In this article, we briefly review the literature on the economics of species extinction, examining what is meant by extinction before explaining how economics has conceptualised this. The initial economics literature on species extinction focuses largely on renewable resources, in particular fisheries, but has subsequently evolved to cover many aspects of biodiversity across all physical scales, employing an increasing array of methodological tools. We also consider aspects of cultural and societal extinctions (e.g. local languages, local knowledge) and how this is positively correlated with loss of biodiversity, as well as an economist’s outlook on the potential to re-capture value post-extinction.

Conserving species and achieving the Convention on Biological Diversity's international conservation targets necessitates stopping extinctions, recovering depleted populations and maintaining viable populations. The contribution of ex situ management to species conservation has long been debated, and there is limited information on ex situ management activities available in a format that allows success to be assessed. We therefore gathered information from three sources to explore cases in which ex situ management was considered to have had a positive conservation impact for terrestrial vertebrate species. We (1) reviewed the published literature, (2) examined for which taxa ex situ management had contributed to the downlisting of species on the IUCN Red List and (3) surveyed a global network of ex situ management practitioners. We found that ex situ management has contributed to improvements in conservation status for a range of vertebrate species. Ex situ management was reported as contributing to the downlisting of 18 species on the IUCN Red List over a 10-year period. Across sources, the most common role of ex situ management was the provision of individuals to increase population numbers in situ. The strength of evidence for the impact of ex situ management varied within and among sources. Therefore, for the role of ex situ activities in conservation to be understood fully, and for such interventions to reach their potential, documentation of intended and actual benefits needs to be improved. Better reporting of ex situ activities would enable improved learning, facilitating better targeting of ex situ activities to global species conservation goals.

The correlation between the biomass of forest primates and a chemical index of the average nutritional quality of leaves in tropical forests has been repeatedly documented since 1990. We tested the role played by protein : fibre on lemur biomass in a gallery forest in southern Madagascar. Plant species abundance was determined based on transect censuses. We calculated an average ratio of protein-to-fibre in leaves and an abundance-weighted ratio, i.e. the mean weighted by the basal area of tree species, to be compared with the figures available for other forest ecosystems in Madagascar and a number of anthropoid habitats. Lemur densities were evaluated through compilation of previous studies made from prior to 1975 and up until 2011 based on strip censuses and/or identification of all groups supplemented with new censuses. A high mean ratio of protein to fibre (> 0.4) supports high folivore biomass at 390 kg km−2 (reaching 630 kg km−2 in the closed-canopy forest area) compared with primate communities in other Malagasy forests (protein : fibre: < 0.5; folivore biomass: < 440 kg km−2), as predicted. However, the data corroborate the finding that the total biomass of lemur communities as well as the biomass of folivorous lemur species are low compared with those of African and Asian primate communities for a given protein : fibre ratio. Tree diversity and leaf production do not consistently explain this pattern. In contrast, the extinction of large folivorous lemurs during the past two millennia presumably allowed too little time for smaller-sized species to evolve equally effective morphological and physiological specializations for processing a large range of fibrous foods.

In this paper we examine the number of known populations of 86 bromeliad species recorded in the Atlantic forest of north-east Brazil, to test the following predictions: (1) the current number of populations of most bromeliad species inhabiting the Atlantic forest of north-east Brazil is critically low, (2) the number of extant populations of a particular species is associated with the ecological attributes of the species, and (3) habitat loss determines, at least in part, the current distribution and number of populations of each species. At present there are at least 535 bromeliad populations in this forest but 61.6% of species have <6 populations and 24.4% have only one known population. The mean number of populations per species was significantly lower among species endemic to this part of the Atlantic forest, species recorded in only one vegetation type, forest and inselberg species, and obligatory epiphytic and terrestrial species. We were unable to relocate 41 populations recorded between 1920 and 1996, and populations of 20 species have become locally extinct. For these bromeliads geographic range, habitat specificity and life form appear to determine which species are more vulnerable to extinction. The species that have <6 extant populations include 27 species that are endemic to this forest. These species need to be evaluated for inclusion on both the IUCN and Brazilian Red Lists. Some of these species will only survive if the fragments containing the last populations are declared as protected areas.