• Letter |

    An analysis of 344 species of tetrapods (birds, mammals, reptiles and amphibians) shows that taxa in which the female is heterogametic tend to have a more male-biased sex ratio; the mechanisms driving the association are unclear, but sex-determination systems are likely to have important consequences for the social behaviour and demography of tetrapods.

    • Ivett Pipoly
    • , Veronika Bókony
    •  & András Liker
  • Letter |

    It has been suggested that the negative effects on bees of neonicotinoid pesticides could be averted in field conditions if they chose not to forage on treated nectar; here field-level neonicotinoid doses are used in laboratory experiments to show that honeybees and bumblebees do not avoid neonicotinoid-treated food and instead actually prefer it.

    • Sébastien C. Kessler
    • , Erin Jo Tiedeken
    •  & Geraldine A. Wright
  • Brief Communications Arising |

    • Peiyun Cong
    • , Xiaoya Ma
    •  & Nicholas J. Strausfeld
  • Letter |

    Malaria-carrying mosquitoes nearly disappear in the dry season, yet they reappear suddenly following the first rains; using surveys of mosquito densities, the authors characterize the population dynamics of the three main vector species and use these to infer persistence by long-distance migration in two species and aestivation in the third.

    • A. Dao
    • , A. S. Yaro
    •  & T. Lehmann
  • Letter |

    Here, colonies of social spiders are used to investigate the evolution of a group-level trait, the ratio of individuals with the ‘docile’ versus ‘aggressive’ phenotype in a colony; experimental colonies were generated with varying ratios and established in the wild, revealing group-level selection.

    • Jonathan N. Pruitt
    •  & Charles J. Goodnight
  • Letter |

    A contemporary test of the theory of island biogeography, in which species richness is determined by an island’s area and isolation, shows that geographic area is still a good positive predictor of species richness, but that geographic isolation as a negative predictor has been replaced by economic isolation.

    • Matthew R. Helmus
    • , D. Luke Mahler
    •  & Jonathan B. Losos
  • Letter |

    For the first time under reproducible and fully double-blinded conditions, it is shown that anthropogenic electromagnetic noise below the WHO limits affects a biological system: night-migrating birds lose the ability to use the Earth’s magnetic field for orientation when exposed to anthropogenic electromagnetic noise at strengths routinely produced by commonly used electronic devices.

    • Svenja Engels
    • , Nils-Lasse Schneider
    •  & Henrik Mouritsen
  • Letter |

    Unlike the tidal (in and out) breathing of mammals, bird lungs have unidirectional airflow patterns; here the savannah monitor lizard is shown to have unidirectional airflow too, with profound implications for the evolution of unidirectional airflow in reptiles, predating the origin of birds.

    • Emma R. Schachner
    • , Robert L. Cieri
    •  & C. G. Farmer
  • Article |

    A novel tracking collar provides highly precise location, speed and acceleration data from 367 runs by five cheetahs in the wild; although a top speed of 58 m.p.h. was reported, few runs were above 45 m.p.h. with the average run around 31 m.p.h., and hunting success depended on grip, manoeuvrability and muscle power rather than outright speed.

    • A. M. Wilson
    • , J. C. Lowe
    •  & J. W. McNutt
  • Letter |

    A pair of Drosophila brain cells is identified and its activation alone is found to induce the fly’s complete feeding motor routine when artificially induced; suppressing or ablating these two neurons eliminates the sugar-induced feeding behaviour, but ablation of just one neuron results in asymmetric movements.

    • Thomas F. Flood
    • , Shinya Iguchi
    •  & Motojiro Yoshihara
  • Brief Communications Arising |

    • Romain Garrouste
    • , Gaël Clément
    •  & André Nel
  • Letter |

    New strashilid fossils from the Middle Jurassic epoch of Daohugou, China, show that they are highly specialized flies, and suggest that larval abdominal respiratory gills were retained in adult males, indicating that adult strashilids were probably aquatic or amphibious, with mating occurring in water.

    • Diying Huang
    • , André Nel
    •  & Michael S. Engel
  • Letter |

    Specific manipulation of midbrain dopamine neurons in freely moving rodents shows that their inhibition or excitation immediately modulates depression-like phenotypes that are induced by chronic mild stress, and that their activation alters the neural encoding of depression-related behaviours in the nucleus accumbens.

    • Kay M. Tye
    • , Julie J. Mirzabekov
    •  & Karl Deisseroth
  • Letter |

    Studying six vespertilionid bat species of different sizes to investigate the reason why smaller bats have higher frequency echolocation calls, a model is put forward that the size/frequency range is modulated by the need to maintain a focused, highly directional echolocation beam.

    • Lasse Jakobsen
    • , John M. Ratcliffe
    •  & Annemarie Surlykke
  • Article |

    Simultaneous electrophysiological recordings in hippocampus and neural-activity-triggered whole-brain imaging in the monkey show that most of the cerebral cortex is activated during the fast hippocampal oscillations (ripples), whereas most diencephalic, midbrain and brainstem regions are inhibited; this may function to optimize information transfer from hippocampus to cortex during off-line memory consolidation.

    • N. K. Logothetis
    • , O. Eschenko
    •  & A. Oeltermann
  • Article |

    Mice lacking 4E-BP2, an eIF4E repressor, display increased translation of neuroligins; the mice also show autism-related behaviours and alterations in hippocampal synaptic activity, and these are reversed by normalization of eIF4E activity or neuroligin 1 levels.

    • Christos G. Gkogkas
    • , Arkady Khoutorsky
    •  & Nahum Sonenberg
  • Letter |

    High-speed tracking of effortful responses and neuronal activity in rats during a forced swim test identifies medial prefrontal cortex (mPFC) neurons that respond during escape-related swimming but not normal locomotion, and optogenetics shows that mPFC neurons projecting to the brainstem dorsal raphe nucleus, which is implicated in depression, modulate this behavioural response to challenge

    • Melissa R. Warden
    • , Aslihan Selimbeyoglu
    •  & Karl Deisseroth
  • Letter |

    Examination of spatial representations in the entorhinal cortex of monkeys performing a visual memory task reveals individual neurons that emit action potentials when the monkey fixates multiple discrete locations in the visual field, and suggests that entorhinal cortex neurons encode space during visual exploration, even without locomotion.

    • Nathaniel J. Killian
    • , Michael J. Jutras
    •  & Elizabeth A. Buffalo
  • Letter |

    Dopamine is synonymous with reward in mammals but associated with aversive reinforcement in insects, where reward seems to be signalled by octopamine; here it is shown that flies have discrete populations of dopamine neurons representing positive or negative values that are coordinately regulated by octopamine.

    • Christopher J. Burke
    • , Wolf Huetteroth
    •  & Scott Waddell
  • Letter |

    Chronic exposure of bumblebees to two pesticides (a neonicotinoid and a pyrethroid) independently and in combination, at concentrations approximating field-level exposure, impairs natural foraging behaviour and increases worker mortality, with knock-on effects for brood development and colony success.

    • Richard J. Gill
    • , Oscar Ramos-Rodriguez
    •  & Nigel E. Raine
  • Article |

    Through the use of a combination of state-of-the-art techniques, different populations of ventral tegmental area dopamine neurons in the mouse are shown to form separate circuits with distinct connectivity: neurons receiving input from the laterodorsal tegmentum and lateral habenula are found to mediate reward and aversion, respectively.

    • Stephan Lammel
    • , Byung Kook Lim
    •  & Robert C. Malenka
  • Article
    | Open Access

    The sequencing and assembly of the highly polymorphic oyster genome through a combination of short reads and fosmid pooling, complemented with extensive transcriptome analysis of development and stress response and proteome analysis of the shell, provides new insight into oyster biology and adaptation to a highly changeable environment.

    • Guofan Zhang
    • , Xiaodong Fang
    •  & Jun Wang
  • Letter |

    The fossil of a complete insect from the Late Devonian period (approximately 365 million years ago) is presented; it was terrestrial, but its features suggest that modern winged insects had already started to diversify at that early date.

    • Romain Garrouste
    • , Gaël Clément
    •  & André Nel
  • Letter |

    This phylogenomic study shows that core muscle proteins were already present in unicellular organisms before the origin of multicellular animals, and supports a convergent evolutionary model for striated muscles in which new proteins are added to ancient contractile apparatus during independent evolution of bilaterians and some non-bilaterians, resulting in very similar ultrastructures.

    • Patrick R. H. Steinmetz
    • , Johanna E. M. Kraus
    •  & Ulrich Technau
  • Article |

    Consumption rates vary substantially between consumers searching in three dimensions (for example, arboreal and pelagic zones), with consumption rates scaling superlinearly with consumer body mass, and those searching in two dimensions (for example, terrestrial and benthic zones), with consumption rates scaling sublinearly with consumer body mass.

    • Samraat Pawar
    • , Anthony I. Dell
    •  & Van M. Savage
  • Letter |

    Three-dimensional reconstruction and modelling of limb joint mobility in the early tetrapod Ichthyostega is used to provide insights into an important step in vertebrate evolution—the transition from swimming to walking.

    • Stephanie E. Pierce
    • , Jennifer A. Clack
    •  & John R. Hutchinson
  • Letter |

    In Bengalese finches, a basal ganglia circuit, the anterior forebrain pathway, can covertly acquire the ability to adaptively modify song without contributing to song production during practice or training.

    • Jonathan D. Charlesworth
    • , Timothy L. Warren
    •  & Michael S. Brainard
  • Article |

    Genetically encoded neural activity markers were used in mice to simultaneously follow large populations of motor cortex neurons during sensorimotor learning, revealing that spatially intermingled neurons represent either sensory or motor behaviour, with population-level representations of subsets of motor programs strengthening as training progressed.

    • D. Huber
    • , D. A. Gutnisky
    •  & K. Svoboda
  • Letter |

    Behavioural, neurogenetic and molecular studies of circadian 24-hour rhythms in fruitflies kept in semi-confinement outdoors challenge our established laboratory-based views of the relative importance of sources of rhythmic entrainment, including temperature, photoperiod and moonlight, as well as the role of some of the underlying clock genes in regulating circadian behaviour in the wild.

    • Stefano Vanin
    • , Supriya Bhutani
    •  & Charalambos P. Kyriacou
  • Letter |

    In hoverflies with a small body size, even imperfect Batesian mimicry suffices to limit predation because they are not subject to particularly intense selection.

    • Heather D. Penney
    • , Christopher Hassall
    •  & Thomas N. Sherratt
  • Letter |

    Comparison of real lizards with a robotic version and a dinosaur model shows that lizards use their tails to control body pitch in aerial motion by means of transfer of angular momentum from the body to the tail.

    • Thomas Libby
    • , Talia Y. Moore
    •  & Robert J. Full