Forgotten women of Paleontology: Elizabeth Anderson Gray

Elizabeth Anderson Gray (1831 – 1924) Image: The Trustees of the Natural History Museum, London

The nineteen century was the “golden age” of Geology. The Industrial Revolution ushered a period of canal digging and major quarrying operations. These activities exposed sedimentary strata and fossils, and the study of the Earth became central to the economic and cultural life of  Great Britain. The most popular aspect of geology was  the collecting of fossils and minerals and the nineteenth-century geology, often perceived as the sport of gentlemen,was in fact, “reliant on all classes”. Women were free to take part in collecting fossils and mineral specimens, and they were allowed to attend lectures but they were barred from membership in scientific societies. It was common for male scientists to have women assistants, but most of them went unacknowledged and become lost to history.  However, some women found the way to avoid that fate. One of those women was Elizabeth Anderson Gray.

Born in Alloway, Ayrshire, on February 21, 1831, Elizabeth Anderson Gray  is considered as one of the foremost Scottish fossil collectors of the late 19th and early 20th centuries. She had little formal schooling but as a girl joined her father, Thomas Anderson, in his hobby of fossil collecting. In 1856, she married a Glasgow banker, Robert Gray, co-founder of The Natural History Society of Glasgow. She took a geology course for women at Glasgow University and she trained her children to document their findings too. She was also friend of Jane Longstaff, a British malacologist and expert in fossil gastropods of the Palaeozoic. The Gray collections, considered important in studies of Ordovician fauna, were sold to institutions. In 1920 a major part of the collection was acquired by the British Museum for £2250. Charles Lapworth, in his work on the ‘Girvan Succession’ referred extensively to E. Gray’s collection in his stratigraphical correlations.

In 1900, Elizabeth Gray was made an honorary member of the Geological Society of Glasgow for her many contributions, and in 1903, she was awarded the Murchison geological fund in recognition of her skilful services to geological science. She continued gathering fossils until her death on 1924.

 

References:

BUREK, C. V. & HIGGS, B. (eds) The Role of Women in the History of Geology. Geological Society, London, Special Publications, 281, 1–8. DOI: 10.1144/SP281.1.

M. R. S. Creese (2007), Fossil hunters, a cave explorer and a rock analyst: notes on some early women contributors to geology, Geological Society, London, Special Publications, 281, 39-49. https://doi.org/10.1144/SP281.3

 

An early juvenile enantiornithine specimen from the Early Cretaceous of Spain

The slab and counterslab of MPCM-LH-26189

Mesozoic remains of juvenile birds are rare. To date, the only records are from the Early Cretaceous of China and Spain, from the mid-Cretaceous of  Myanmar, and from the Late Cretaceous of Argentina and Mongolia. The most recent finding from the Early Cretaceous of Las Hoyas, Spain, provide an insight into the osteogenesis of the Enantiornithes, the most abundant clade of Mesozoic birds. Previous records of Enantiornithes from the Las Hoyas fossil site include: Eoalulavis hoyasi, Concornis lacustris, and Iberomesornis romerali.

The latest specimen, MPCM-LH-26189, a nearly complete and largely articulated skeleton (only the feet, most of its hands, and the tip of the tail are missing), is very small. The specimen died around the time of birth, a crucial moment to study the osteogenesis in birds. The skull, is partially crushed, and is large compared to the body size. The braincase is fractured. The frontals and the parietals form a uniformly curved cranial vault. The cerebrocast shows a very slight inflation, suggesting that the cerebral anatomy of MPCM-LH-26189 falls in between that of the Archaeopteryx, and the putative basal ornithurine Cerebavis, whose telencephalic expansion is close to most extant birds. The cervical series is composed of 9 vertebrae. There are 10  thoracic vertebrae, and the sacrum appears to be composed of 5–6 vertebrae. The prezygapophyses of the mid-thoracic vertebrae extend beyond the cranial articular surface. The thoracic ribs are joint to the thoracic vertebrae. The two coracoids, the furcula, and three sternal ossifications are preserved. The furcula is Y-shapped. Both humeri, ulnae, and radii are also preserved.

Reconstruction of MPCM-LH-26189 by Raúl Martín

The osteohistological analysis of the left humerus shows a dense pattern of longitudinal grooves. Those grooves correspond to primary cavities, which open onto the surface of the cortex in young and fast-growing bone. The shaft of the tibia and radius show very-thin cortices. In addition,  the primary nature of the vascularisation, the round shape of the osteocytes lacunae and the uneven peripheral margin of the medullary cavity (with no endosteal bone), strongly suggests that the bone was actively growing when the bird died.

Enantiornithines show a mosaic of characters, reflecting their intermediate phylogenetic position between the basal-pygostylians and modern bird. In this clade, the sternum adopts an elaborate morphology, and in adult Enantiornithes, no more than eight free caudal vertebrae precede the pygostyle. The differences observed in the ossification of the sternum and the number of free caudal vertebrae in MPCM-LH-26189, when it compared to other juvenile enantiornithines, reveal a clade-wide asynchrony in the sequence of ossification of the sternum and tail, suggesting that the developmental strategies of these basal birds may have been more diverse than previously thought.

References:

Fabien Knoll, et al., “A diminutive perinate European Enantiornithes reveals an asynchronous ossification pattern in early birds,” Nature Communications, volume 9, Article number: 937 (2018) doi:10.1038/s41467-018-03295-9

Chiappe, L. M., Ji, S. & Ji, Q. Juvenile birds from the Early Cretaceous of China: implications for enantiornithine ontogeny. Am. Mus. Novit. 3594, 1–46 (2007).