Whale swimming evolution recorded in vertebral microanatomy from the Eocene to present

Whale locomotion changed significantly from land-living ancestors, via semi-aquatic taxa, to today's fully aquatic species. The vertebral column is important for swimming, and this study focuses on t...

onlinelibrary.wiley.com

Lateral palatal foramina are ubiquitous across fossil whales and shared with hippos

Abstract. Lateral palatal foramina have been proposed as osteological correlates for baleen in fossil mysticetes. A recent study reported significantly ele

royalsocietypublishing.org

New data on the morphology, taphonomy, and phylogeny of Saghacetus osiris (Cetacea, Basilosauridae) and other archaeocetes from the late Eocene (Priabonian) of Fayoum, Egypt

In this study, we present a revision of so far unpublished archaeocete material from the middle to late Eocene deposits of Al-Fayoum (41.2–33.9 Ma), including two previously unpublished incomplete ...

tandfonline.com

Navigating AI-Accelerated Science: An Intellectual Virtue Approach to Responsible Inquiry | Episteme | Cambridge Core

Navigating AI-Accelerated Science: An Intellectual Virtue Approach to Responsible Inquiry

cambridge.org

These Birds Are Louder Than Elephants, Jackhammers and Chain Saws (Gift Article)

A new study has identified two species of Brazilian birds, the bare-throated bellbird and the red-legged seriema, as the loudest in nature.

nytimes.com

onlinelibrary.wiley.com

philsci-archive.pitt.edu

Buried, or maybe not: adherence to evidential standards in paleoanthropology - Biology & Philosophy

This paper examines how evidential standards are constructed, interpreted, and enforced in paleoanthropology and funerary archaeology, focusing on claims of deliberate burial practices in Homo naledi....

link.springer.com

A new species of Miophyseter (Cetacea, Odontoceti, Physeteroidea) from the Miocene of Japan

Three fossil physeteroids have been recovered from the Lower to Middle Miocene of Japan. Here, we describe and diagnose these specimens as a new species of the genus Miophyseter, M. gunmaensis, sp....

tandfonline.com

Real-Time Public Report Helps Cascadia Free Entangled Whale off Westport, Washington - https://cascadiaresearch.org

Entangled humpback whale off Westport, Washington, found and reported by sport fishermen, Sam Azar IV. Cascadia Research Collective, NOAA permit #24359. A rapid response by Cascadia Research Collectiv...

cascadiaresearch.org

Rates of passerine body plan evolution in time and space

Nature Ecology & Evolution - A reconstruction of the evolutionary history of passerine body plans over the past ~50 Myr shows rare bursts of phenotypic innovation near the origin of major...

rdcu.be

Sternal anatomy reflects feeding style in mysticete cetaceans - Journal of Mammalian Evolution

Baleen whales (mysticetes) underwent a profound transition from raptorial to filter feeding early in their history, allowing the exploitation of new food sources and environments. Their key structural innovation, baleen, is rarely fossilized, complicating reconstruction of the transition. Muscles used in food capture, locomotion, and respiration are anchored on developmentally discrete subunits of the sternum in living mysticetes, offering a novel approach for predicting muscle function and feeding style in extinct taxa. Elliptic Fourier Analysis was used to test the relationship between sternal shape and feeding style in extant balaenopteroid mysticetes. Results indicate that sternal shape changes during the ontogenetic transition from juvenile nursing to adult filter feeding and differs among adults of species with different styles of filter feeding, providing support for the use of sternal structure to predict the feeding habits of extinct taxa. The dense, block-shaped presterna and multiple sternebrae of early mysticetes suggest that they used static buoyancy control in nearshore environments and lacked the thoracic compliance necessary for deep diving. Variably enlarged sternohyoid muscle fields indicate that they all employed suction during prey capture. In sharp contrast, eomysticetes have osteoporotic, planar sterna without sternebrae and minimal sternohyoid fields, signaling deeper water habitats, diving facilitated by thoracic compliance, and little or no suction. Taxa crownward of eomysticetes display novel elaborations of the sternohyoid and sternocephalic muscle fields that characterize continuous and intermittent ram-feeding in living balaenopteroids.

doi.org

A basal representative of Cetacea from the Eocene of India - Nature Ecology & Evolution

The authors report Kalakocetus aurorae, a new fossil species from India, which is phylogenetically recovered as the most basal member of Cetacea and which bridges a dental morphological gap between ce...

doi.org

The Geology and Vertebrate Paleontology of Calvert Cliffs, Maryland, USA – Volume 3: Elephants, Land Mammals, and Seals

In this third volume in the series on the Miocene vertebrate fauna from Calvert Cliffs, Maryland, USA, the three chapters detail the historical record and taxonomy of Miocene elephants, all other known land mammals, and seals. Chapter 1 examines the remains of Miocene elephants (Gomphotheriidae). The earliest record of a gomphothere from the Chesapeake Group was a molar collected near Governor Run, Calvert County. Other gomphothere molars scattered throughout the area extend up through the Miocene Choptank, St. Marys, and Eastover Formations. There are at least four taxa (probably five) of Gomphotheriidae from the Chesapeake Group: Gomphotherium calvertense; a new genus and species from the Choptank Formation; aff. Stenobelodon floridanus; an unidentified Gomphotheriidae; and, tentatively, Rhynchotherium. Chapter 2 reviews the hundreds of fossils of terrestrial mammals collected from the Mid-Atlantic Coastal Plain deposits of the Chesapeake Group. Most of these isolated remains originated from marine deposits of the Calvert and St. Marys Formations. The fauna represents a diverse and, in some instances, unusual assemblage ranging from the late early Miocene through to the early Pliocene. It illustrates a shift in terrestrial faunas from an open marine shelf environment bordered by a drier prairie and patchy forest to a more closed coastal marine and estuarine environment bordered by a humid and forested environment. Chapter 3 provides a review of the earless seals (Phocidae). Five extinct phocids have been recognized based on differences in their limb bones: the monachines Magnotherium johnsii, Terranectes magnus, and Terranectes parvus and the phocines Leptophoca amphiatlantica and Leptophoca lenis (later grouped into Leptophoca proxima). Unfortunately, long bones are not a sufficient basis on which to name new taxa, and consequently, recent research on variation in appendicular bones of Phocidae resulted in the validity of M. johnsii and both Terranectes species being questioned. However, one unnamed species of Monachinae is recognized from the Miocene of the Chesapeake Group. Leptophoca proxima includes two distinct morphotypes of humeri, warranting separating L. lenis from specimens of L. proxima. Accordingly, at least two phocine species are present in the Miocene strata of the Chesapeake Group, with a total of three morphotypes of Phocidae.

doi.org

Toothed whales independently evolve specialized suction feeding without converging on skull shape

Specialized suction feeders independently evolved in several odontocete (toothed whale) lineages, with paradigmatic examples in sperm whales and beaked whales. Although little is known about feeding b...

peerj.com

Sperm whales caught headbutting each other on camera for the first time

Drone footage has revealed sperm whales headbutting each other—something scientists had only speculated about until now. Surprisingly, it’s younger whales doing it, not the giant males researchers…

sciencedaily.com

Long bone variability in true seals (Mammalia, Phocidae), with implications for understanding their fossil record

Historically, humeri and femora have been treated as diagnostic elements for fossil phocid (Carnivora, Pinnipedia, Phocidae) identification. This resulted in the naming of a plethora of extinct phoci...

anatomypubs.onlinelibrary.wiley.com

New evidence of a toothed mysticete from the Vaqueros Formation of California fills a gap in the palaeobiogeographic range of Aetiocetidae

Abstract. Extant baleen whales (Mysticeti) are toothless aquatic predators that use keratinous baleen plates to capture and filter smaller prey. Although a

royalsocietypublishing.org