A practical tool for assessing ecosystem services enhancement and degradation associated with invasive alien species

Current approaches for assessing the effects of invasive alien species (IAS) are biased toward the negative effects of these species, resulting in an incomplete picture of their real effects. This can result in an inefficient IAS management. We address this issue by describing the INvasive Species Effects Assessment Tool (INSEAT) that enables expert elicitation for rapidly assessing the ecological consequences of IAS using the ecosystem services (ES) framework. INSEAT scores the ecosystem service “gains and losses” using a scale that accounted for the magnitude and the reversibility of its effects. We tested INSEAT on 18 IAS in Great Britain. Here, we highlighted four case studies: Harmonia axyridis (Harlequin ladybird), Astacus leptodactylus (Turkish crayfish), Pacifastacus leniusculus (Signal crayfish) and Impatiens glandulifera (Himalayan balsam). The results demonstrated that a collation of different experts’ opinions using INSEAT could yield valuable information on the invasive aliens’ ecological and social effects. The users can identify certain IAS as ES providers and the trade-offs between the ES provision and loss associated with them. This practical tool can be useful for evidence-based policy and management decisions that consider the potential role of invasive species in delivering human well-being.</p

Genetic conflict and conditional altruism in social aphid colonies

Although kin selection is central to the modern study of social evolution, recent studies of social species have revealed that no simple relationship exists between levels of kinship and sociality. The soldier-producing aphids are unique among highly social animals because, barring movement by aphids between colonies, they occur in clonal groups of genetically identical individuals. Potentially, clonality simplifies efforts to understand social evolution in aphids by obviating issues of intragroup conflict. However, we report here high levels of clonal mixing and conflict in an aphid society. The gall-dwelling colonies of a social aphid species (Pemphigus obesinymphae) are not pure clones, but are invaded by large numbers of aphids from other clones. Intruders behave and develop selfishly once they have invaded a colony of nonkin. They refrain from risky defensive behaviors and accelerate their own development into reproductive rather than defensive stages. This conditionality in the social life of P. obesinymphae reveals complex dynamics and a degree of behavioral plasticity not previously known in aphid societies

Frogs flee from the sound of fire.

Fire has an important role in the sensory ecology of many animals. Using acoustic cues to detect approaching fires may give slow-moving animals a head start when fleeing from fires. We report that aestivating juvenile reed frogs (Hyperolius nitidulus) respond to playbacks of the sound of fire by fleeing in the direction of protective cover, where they are safe. This is a novel response to fire not known to occur in other animals. Moreover, we identify the rapid rise-time of the crackling sound of fire as the probable cue used. These results suggest that amphibian hearing not only has evolved through sexual selection, but also must be viewed in a broader context