New Late Jurassic docodontan

New Late Jurassic docodontan fossil (with skull) published in Science.

Evolutionary development in basal mammaliaforms as revealed by a docodontan

Zhe-Xi Luo1,*, Qing-Jin Meng2,*, Qiang Ji3, Di Liu2, Yu-Guang
Zhang2, April I. Neander1

A new Late Jurassic docodontan shows specializations for a
subterranean lifestyle. It is similar to extant subterranean golden
moles in having reduced digit segments as compared to the ancestral
phalangeal pattern of mammaliaforms and extant mammals. The reduction
of digit segments can occur in mammals by fusion of the proximal and
intermediate phalangeal precursors, a developmental process for which
a gene and signaling network have been characterized in mouse and
human. Docodontans show a positional shift of thoracolumbar ribs, a
developmental variation that is controlled by Hox9 and Myf5 genes in
extant mammals. We argue that these morphogenetic mechanisms of modern
mammals were operating before the rise of modern mammals, driving the
morphological disparity in the earliest mammaliaform diversification.




Actually not just one, but two new docodonts were published side by side.

One subterrestrial, which you are referring and one scansorial…

Luo, Z.-X., Meng, Q.-J., Ji, Q., Liu, D., Zhang, Y.-G. & Neander, A. I., 2015: Evolutionary development in basal mammaliaforms as revealed by a docodontan.
–Science: Vol. 347, #6223, pp. 760-764 [doi: 10.1126/science.1260880]

Meng, Q.-J., Ji, Q., Zhang, Y.-G., Liu, D., Grossnickle, D. M. & Luo, Z.-X., 2015: An arboreal docodont from the Jurassic and mammaliaform ecological diversification.
–Science: Vol. 347, #6223, pp. 764-768 [doi: 10.1126/science.1260879]


–Mikko H.