The systematic study of head regeneration in a collection of 40 planarian species provides a framework for the mechanistic understanding of the evolution of regenerative abilities. The proposed hypothesis raises the possibility that a trade-off between egg-laying, asexual reproduction by fission–regeneration and Wnt signalling underlies the existence of the varied head-regeneration abilities observed among planarian species.

See Vila-Farré et al.

Two forms of the red-shouldered soapberry bug Jadera haematoloma — a large-winged dispersal form (top) and a small-winged flightless form (bottom) — inspecting the fruit of the balloon vine Cardiospermum halicacabum. This study documents an understudied form of evolution known as spatial sorting, which promotes rapid change in dispersal and feeding traits following local extinctions (driven in this case by a hurricane).

See Comerford et al.

Comprehensive genome analysis of almost all living individuals of the endangered kākāpō (Strigops habroptilus) may guide efforts to pull this nocturnal, flightless bird in Aotearoa New Zealand back from the brink of extinction. Genomics can help to inform conservation decisions, including prioritizing individuals for translocation and identifying individuals with high disease risk.

See Guhlin et al.

A high-throughput DNA metabarcoding analysis of a grassland ecosystem reveals seasonal dynamism of food-web structure. The study suggests that spider predator species (such as Neoscona scylloides, pictured) with key roles in complex webs of interactions change across seasons.

See Suzuki et al.

A fennec fox mid-stride in the Sahara. An exploration of survival under extreme conditions shows how desert-dwelling foxes have genetically and physiologically adapted to their arid and hyper-arid homes, revealing lessons on the mechanisms of adaptation in the face of desertification and climate change.

See Rocha et al.

The golden snub-nosed monkey (Rhinopithecus roxellana) belongs to the Old World monkeys, which make up the largest family of primates. A comparative genomics study across 29 primates reveals that the Y chromosome exhibits highly diverse genomic features across lineages.

See Zhou et al

The migratory locust, Locusta migratoria, develops into solitary (above) or gregarious (below) phases depending on population density. Because of PLIN2-induced ectopic lipid accumulation, the muscles of gregarious locusts display a faster decline in physiological and metabolic functions than those of solitary locusts. The phase-related ageing plasticity in locusts provides a novel model system for studying ecological ageing.

See Guo et al.

A male Southern Resident killer whale off San Juan Island, Washington, USA. Unlike most North Pacific killer whale populations, the population of endangered Southern Residents has remained small and declined since the 1990s — despite 50 years of legal protection and conservation efforts. Genomic and demographic analyses reveal that inbreeding has reduced survival and limited the growth and recovery of the population.

See Kardos et al.

Tagged Antarctic minke whales (Balaenoptera bonaerensis), which are the smallest lunge feeders, surface in a group before 9 feeding dives in 3 minutes. Cade et al. found that these ultra-high feeding rates (which can exceed 200 lunges per hour at night) barely enable the whales to meet their expected metabolic needs, and suggest that biomechanical, environmental and physiological constraints would not allow lunge feeding as a strategy in smaller species.

See Cade et al

Most animals spend the majority of their lives within a familiar home range. Cognitive tests on pheasants (Phasianus colchicus) support the hypothesis that spatial reference memory underlies the ability to develop a home range, as well as suggesting its critical role in allowing birds to become familiar enough with the landscape to avoid ambush predators.

See Heathcote et al.

Hillside covered with quaking aspens (Populus tremuloides Michx.) displaying their autumn colour near Lockett Meadow in Flagstaff, Arizona (USA). A long-term trend towards later autumn senescence persists in parallel with a trend towards increasing photosynthesis, despite their negative relationship at the interannual scale. This shift suggests a gradual acclimation of phenology that relieves leaf longevity constraints observed at the short-term.

See Marqués et al

A hoverfly of the genus Eristalis foraging for pollen. A comparison of historical and current data reveals that the interactions between plants and pollinators have changed drastically over the past 120 years in subarctic Finland. Hoverflies and specialist species in particular have declined, and flies from the family Muscidae now provide a large proportion of pollination services.

See Zoller et al