Results 101 to 110 of about 36,421 (247)
Abstract A recent debate has emerged between Caspar et al. (2024) and Herculano‐Houzel (2023) on inferring extinct dinosaur cognition by estimating brain neuron counts. While thought‐provoking, the discussion largely overlooks the function of cognition, as well as partly neglects the difficulties involved in estimating neuron numbers, which according ...
Thomas Rejsenhus Jensen +7 more
wiley +1 more source
Abstract The study of morphological evolution is fundamentally tied to ontogeny, yet studies of these heterochronic processes in the fossil record are rare. Fossils belonging to an ontogenetic series are difficult to assign to an ontogenetic stage due to inconsistent proxies for skeletal ages, challenging to taxonomically assign due to morphological ...
Erika R. Goldsmith, Michelle R. Stocker
wiley +1 more source
Abstract The upper carbonate concretion levels of the Romualdo Formation (Aptian, Brazil) have yielded several theropod dinosaur remains, including spinosaurids and the coelurosaurs Santanaraptor placidus and Mirischia asymmetrica, the phylogenetic affinities of which are controversial.
Rafael Delcourt +4 more
wiley +1 more source
Pathways and timescales of Southern Ocean hydrothermal iron and manganese transport
Scarcity of iron and manganese limits the efficiency of the biological carbon pump over large areas of the Southern Ocean. The importance of hydrothermal vents as a source of these micronutrients to the euphotic zone of the Southern Ocean is debated ...
Antony J. Birchill +10 more
doaj +1 more source
Chemoautotrophy at Deep-Sea Vents: Past, Present, and Future [PDF]
Chemolithoautotrophic microorganisms are at the nexus of hydrothermal systems by effectively transferring the energy from the geothermal source to the higher trophic levels.
Stefan M. Sievert, Costantino Vetriani
doaj
Abstract The ray‐finned fishes include one out of every two species of living vertebrates on Earth and have an abundant fossil record stretching 380 million years into the past. The division of systematic knowledge of ray‐finned fishes between paleontologists working on extinct animals and neontologists studying extant species has obscured the ...
Jack Stack
wiley +1 more source
Abstract Pterosaur dental biology remains poorly understood despite its importance for comprehending feeding strategies and flight adaptations. Here, we present the first comprehensive histological analysis of an ornithocheiriform pterosaur tooth from the Lower Cretaceous Crato Formation (Santana Group, Northeast Brazil).
Tito Aureliano +3 more
wiley +1 more source
Biogeochemical Processes at Hydrothermal Vents: Microbes and Minerals, Bioenergetics, and Carbon Fluxes [PDF]
Hydrothermal vents are among the most biologically active regions of the deep ocean. However, our understanding of the limits of life in this extreme environment, the extent of biogeochemical transformation that occurs in the crust and overlying ocean ...
James F. Holden +4 more
doaj
Abstract Hadrosaurid dinosaurs are generally regarded as “crested” or “non‐crested” depending on the presence or absence of a bony cranial crest. At least one supposedly “non‐crested” hadrosaur is known to have possessed a soft tissue cranial crest (or comb), based on an exceptionally preserved “mummified” specimen. Here we redescribe this specimen and
Henry S. Sharpe +4 more
wiley +1 more source
Background: The biomechanical behaviour of mandibular Ti-Zr mini-implant (MDI) retained overdentures is influenced by implant number, loading conditions, and mucosal thickness. This study assessed the effect of mucosal thickness and other factors on peri-
Asja Čelebić +5 more
doaj +1 more source

