The avifauna of the forest mosaic habitats of the Mariarano region, Mahajanga II district, north-west Madagascar

Background: The West Malagasy dry forests support numerous endemic species and experience heavy anthropogenic pressures, yet remain very poorly studied. Further research is required to understand species distributions and overall diversity in these threatened forest ecosystems.Objectives: We aimed to provide a description of the avifaunal community of a particular dry forest, Mariarano forest, north-western Madagascar, as well as other habitats that are heavily integrated with these Forests. The study site possesses a highly endemic bird community and is under severe environmental pressure, but remains poorly explored.Method: We compiled all records from a 9-year (2010–2018) bird survey data set (the most extensive compiled from a Madagascan dry forest to date), which yielded data from a combination of point count and mist-netting protocols. This was further supplemented by approximately 4384 h of opportunistic observation effort.Results: In total, 95 species were detected, including 63 regional endemics (66.3% of all species), 2 local endemics and 7 Threatened or Near-Threatened species.Conclusion: We highlight the forest mosaic habitats of Mariarano as a potential new Important Bird Area, given the regional importance of its endemic avifauna.

Ontogenetic Habitat Usage of Juvenile Carnivorous Fish Among Seagrass-Coral Mosaic Habitats

Seagrass beds and coral reefs are both considered critical habitats for reef fishes, and in tropical coastal regions, they often grow together to form “mosaic” habitats. Although reef fishes clearly inhabit such structurally complex environments, there is little known about their habitat usage in seagrass-coral mosaic habitats. The goal of this study was to examine potential factors that drive habitat usage pattern by juvenile reef fishes. We quantified (1) prey availability, (2) potential competitors, and 3) predators across a gradient of mosaic habitats (n = 4 habitat types) for four dominant carnivorous fishes (lethrinids and lutjanids) in the main recruitment season at Dongsha Island, South China Sea. We found that the coral-dominated habitats had not only a higher availability of large crustacean prey but also a higher abundance of competitors and predators of juvenile fishes. Food availability was the most important factor underlying the habitat usage pattern by lethrinids and lutjanids through ontogeny. The predation pressure exhibited a strong impact on small juvenile lethrinids but not on larger juveniles and lutjanids. The four juvenile fishes showed distinct habitat usage patterns through ontogeny. Collectively, mosaic habitats in the back reef system may be linked to key ontogenetic shifts in the early life histories of reef fishes between seagrass beds and coral reefs.

An annotated checklist of the birds of upper Chenab catchment, Jammu & Kashmir, India

Watershed avifaunal inventories are useful in devising management strategies appropriate to the habitat, as well as species conservation. The Chenab River basin forms one of the largest and most important river basins in Jammu & Kashmir. The upper Chenab catchment offers a rich and diverse fauna, especially birds, owing to variety of habitats, different climatic regimes, and a wide range of altitude,. We present an avifaunal list of four watersheds—Bhot, Marusudar, Kalnai and Neeru of the Chenab River basin including Kishtwar Town and the surrounding area of the upper Chenab catchment over an elevation range of 820–4,500 m. The list includes 251 species belonging to 60 families and 150 genera of which six are globally threatened, 127 residents, 124 migrants and three new to the state. The paper also describes species-wise habitat occupancy, feeding behaviour, migratory status and abundance of the avifauna. The study reveals that mosaic habitats comprising forests, riverbeds, rangelands and rocky outcrops are crucial for the conservation of birds in the region.

Revision of Isoplenodia Prout, 1932 with new records from continental Africa (Lepidoptera: Geometridae, Sterrhinae)

Three new species of Isoplenodia Prout, 1932 are described and illustrated from continental Africa, expanding the taxonomic scope and known geographic distribution of this previously endemic, monotypic Madagascan genus of geometrid moths. The new species are: I. vidalensis Sihvonen & Staude sp. n., from eastern South Africa; I. kisubiensis Sihvonen & Staude sp. n., from southern Uganda; and I. arabukoensis Sihvonen & Staude sp. n., from southeastern Kenya, central Zimbabwe and southwestern Rwanda. The paucity of available data suggest that the African species may be associated with wet forest or marsh mosaic habitats. Adults and genitalia of all known Isoplenodia species are illustrated, and the systematic position of the genus in relation to other genera in the tribe Scopulini is discussed.

Brain evolution in Homo: The “radiator” theory

The “radiator” theory of brain evolution is proposed to account for “mosaic evolution” whereby brain size began to increase rapidly in the genus Homo well over a million years after bipedalism had been selected for in early hominids. Because hydrostatic pressures differ across columns of fluid depending on orientation (posture), vascular systems of early bipeds became reoriented so that cranial blood flowed preferentially to the vertebral plexus instead of the internal jugular vein in response to gravity. The Hadar early hominids and robust australopithecines partly achieved this reorientation with a dramatically enlarged occipital/marginal sinus system. On the other hand, hominids in the gracile australopithecine through Homo lineage delivered blood to the vertebral plexus via a widespread network of veins that became more elaborate through time. Mastoid and parietal emissary veins are representatives of this network, and increases in their frequencies during hominid evolution are indicative of its development. Brain size increased with increased frequencies of mastoid and parietal emissary veins in the lineage leading to and including Homo, but remained conservative in the robust australopithecine lineage that lacked the network of veins. The brain is an extremely heatsensitive organ and emissary veins in humans have been shown to cool the brain under conditions of hyperthermia. Thus, the network of veins in the lineage leading to Homo acted as a radiator that released a thermal constraint on brain size. The radiator theory is in keeping with the belief that basal gracile and basal robust australopithecines occupied distinct niches, with the former living in savanna mosaic habitats that were subject to hot temperatures and intense solar radiation during the day.