The significant extinctions in Earth history have largely been unpredictable in terms of what species perish and what traits make species susceptible. The extinctions occurring during the late Pleistocene are unusual in this regard, because they were strongly size-selective and targeted exclusively large-bodied animals (i.e., megafauna, >1 ton) and disproportionately, large-bodied herbivores. Because these animals are also at particular risk today, the aftermath of the late Pleistocene extinctions can provide insights into how the loss or decline of contemporary large-bodied animals may influence ecosystems. Here, we review the ecological consequences of the late Pleistocene extinctions on major aspects of the environment, on communities and ecosystems, as well as on the diet, distribution and behavior of surviving mammals. We find the consequences of the loss of megafauna were pervasive and left legacies detectable in all parts of the Earth system. Furthermore, we find that the ecological roles that extinct and modern megafauna play in the Earth system are not replicated by smaller-bodied animals. Our review highlights the important perspectives that paleoecology can provide for modern conservation efforts.

Currently, there is little comparative data on ‘efficiency’ of different engineering species, i.e. species richness, density and biomass of the associated organisms that have been supported by engineering species. The use of fouling communities makes it possible to compare the efficiency of different engineering species under the same conditions, which is necessary to obtain correct estimates and difficult to do when studying natural bottom communities. In this study, we have analysed the fouling communities in four different mussel culture farms in the White Sea to test the following hypotheses. (1) Different engineering species (mussel Mytilus edulis, solitary ascidian Styela rustica, sponge Halichondria panicea) have different assemblages of the associated vagile fauna. (2) Mytilus edulis is the most efficient engineering species, i.e. species richness, species diversity, density and biomass of the associated vagile fauna is higher in the mussel communities than in those dominated by Styela rustica or Halichondria panicea. The first hypothesis was confirmed, while the second was rejected. In all the culture farms studied, all parameters of the mussel-associated vagile fauna were not higher and in most cases were even lower than those of the fauna associated with ascidians or sponges. The reason for this seems to be the very dense packing of mussels in patches. Therefore, Mytilus edulis is not the most efficient engineering species among fouling organisms, at least in the conditions of the subarctic White Sea. The data obtained are particularly important in view of the ever-increasing volume of anthropogenic substrate and fouling communities in coastal marine ecosystems.

Ecosystem engineers such as the Antarctic scallop (Adamussium colbecki) shape marine communities. Thus, changes to their lifespan and growth could have far-reaching effects on other organisms. Sea ice is critical to polar marine ecosystem function, attenuating light and thereby affecting nutrient availability. Sea ice could therefore impact longevity and growth in polar bivalves unless temperature is the overriding factor. Here, we compare the longevity and growth of A. colbecki from two Antarctic sites: Explorers Cove and Bay of Sails, which differ by sea-ice cover, but share similar seawater temperatures, the coldest on Earth (-1.97°C). We hypothesize that scallops from the multiannual sea-ice site will have slower growth and greater longevity. We found maximum ages to be similar at both sites (18–19 years). Growth was slower, with higher inter-individual variability, under multiannual sea ice than under annual sea ice, which we attribute to patchier nutrient availability under multiannual sea ice. Contrary to expectations, A. colbecki growth, but not longevity, is affected by sea-ice duration when temperatures are comparable. Recent dramatic reductions in Antarctic sea ice and predicted temperature increases may irrevocably alter the life histories of this ecosystem engineer and other polar organisms.

Introduced species can have strong ecological, social and economic effects on their non-native environment. Introductions of megafaunal species are rare and may contribute to rewilding efforts, but they may also have pronounced socio-ecological effects because of their scale of influence. A recent introduction of the hippopotamus Hippopotamus amphibius into Colombia is a novel introduction of a megaherbivore onto a new continent, and raises questions about the future dynamics of the socio-ecological system into which it has been introduced. Here we synthesize current knowledge about the Colombian hippopotamus population, review the literature on the species to predict potential ecological and socio-economic effects of this introduction, and make recommendations for future study. Hippopotamuses can have high population growth rates (7–11%) and, on the current trajectory, we predict there could be 400–800 individuals in Colombia by 2050. The hippopotamus is an ecosystem engineer that can have profound effects on terrestrial and aquatic environments and could therefore affect the native biodiversity of the Magdalena River basin. Hippopotamuses are also aggressive and may pose a threat to the many inhabitants of the region who rely upon the Magdalena River for their livelihoods, although the species could provide economic benefits through tourism. Further research is needed to quantify the current and future size and distribution of this hippopotamus population and to predict the likely ecological, social and economic effects. This knowledge must be balanced with consideration of social and cultural concerns to develop appropriate management strategies for this novel introduction.

The ecological ubiquity of parasites and their potential impacts on host behaviour have led to the suggestion that parasites can act as ecosystem engineers, structuring their environment and physical habitats. Potential modification of the relationship between parasites and their hosts by climate change has important implications for how hosts interact with both their biotic and abiotic environment. Here, we show that warming and parasitic infection independently increase rates of bioturbation by a key detritivore in aquatic ecosystems (Gammarus). These findings have important implications for ecosystem structure and functioning in a warming world, as alterations to rates of bioturbation could significantly modify oxygenation penetration and nutrient cycling in benthic sediments of rivers and lakes. Our results demonstrate a need for future ecosystem management strategies to account for parasitic infection when predicting the impacts of a warming climate.

The size at first maturity of the bivalve Brachidontes rodriguezii was estimated in a population located in the northernmost limit of its distribution along Argentinean coast. Specimens were collected in two consecutive reproductive seasons from December 2011 to February 2012 and from December 2012 to February 2013. Individuals were evaluated using biometric and histological analyses of the gonads. This study intended to provide important information about the development of gonadal tissue according to shell length increase. Our results showed immature specimens lack gonads or exhibited groups of cells undergoing mitosis adjacent to the epithelium of the mantle and the tubules of the digestive gland. Male and female gonad development extended to mantle lobes and visceral mass as long as maturation occurred to reach sexual maturity. Using a logistic model our results showed that the size at which 50% of females were mature at a gonadal level was 7.05 mm in shell length; in males, 50% of the population were mature at 8.13 mm in shell length. The minimum shell length at which maturity was observed was 6.99 mm in shell length in females and 6.00 mm in shell length for males.

Frogs are known to occasionally utilize the burrow systems of subterranean rodents, but this phenomenon has previously attracted little attention. We recorded frogs in burrows and in/under the molehills of three African mole-rat species (Bathyergidae, Rodentia) during burrow system mapping in Malawi and Zambia during the dry season. Eight frog species were detected. The most abundant of them, Kassina senegalensis, was found in large numbers in active Ansell's mole-rat nest areas, obviously tolerated by the hosts. We speculate that in areas with prolonged dry seasons mole-rats may increase anuran abundances and diversity.

The present study reports new records of the invasive pygmy mussel Xenostrobus securis in six brackish-water localities in the western Mediterranean. Until now X. securis, whose native range includes southern Australia and New Zealand, was also known from the northern Adriatic Sea and southern France. Along the coast of northern Tuscany (Italy) X. securis invaded brackish-water canals in the area between the port of Leghorn and the mouth of the Arno River. Moreover, this mussel has been found in one inner site of the Gulf of Olbia (north-eastern Sardinia, Italy) and at the mouth of the Fluvià River (northern Catalonia, Spain). As an ecosystem engineer, X. securis is an ecologically important species, heavily altering pre-existing benthic communities. Given that its presence in other western Mediterranean sites is highly possible, we recommend a closer monitoring of brackish-water biotopes.

The discovery of nearly periodic vegetation patterns in arid and semi-arid regionsmotivated numerous model studies in the past decade. Most studies have focused onvegetation pattern formation, and on the response of vegetation patterns to gradients ofthe limiting water resource. The reciprocal question, what resource modifications areinduced by vegetation pattern formation, which is essential to the understanding ofdryland landscapes, has hardly been addressed. This paper is a synthetic review of modelstudies that address this question and the consequent implications for inter-specificplant interactions and species diversity. It focuses both on patch and landscape scales,highlighting bottom-up processes, where plant interactions at the patch scale give rise tospatial patterns at the landscape scale, and top-down processes, where pattern transitionsat the landscape scale affect inter-specific interactions at the patch scale.