Eoarthropleura, previously known only from the Lower Devonian of Germany, is reported here from the Upper Silurian (PHdoli) of Shropshire, England, the Upper Devonian (Frasnian) of New York State, USA, and the Lower Devonian (Emsian) of New Brunswick, Canada. The Shropshire form (E. ludfordensis n. sp.) is the earliest representative of the Arthropleurida. The New York species, originally ascri...

Lungfish, or dipnoans, have a history spanning over 400 million years and are the closest living sister taxon to the tetrapods. Most Devonian lungfish had heavily ossified endoskeletons, whereas most Mesozoic and Cenozoic lungfish had largely cartilaginous endoskeletons and are usually known only from isolated tooth plates or disarticulated bone fragments. There is thus a substantial temporal a...

Tetrapod fossil tracks are known from the Middle Devonian (Eifelian at ca. 397 million years ago--MYA), and their earliest bony remains from the Upper Devonian (Frasnian at 375-385 MYA). Tetrapods are now generally considered to have colonized land during the Carboniferous (i.e., after 359 MYA), which is considered to be one of the major events in the history of life. Our analysis on tetrapod e...

The rarity of Devonian tetrapods and the absence of tetrapods during the first 14 million years of the Mississippian (Romer’s Gap) have inspired hypotheses of fish-tetrapod evolutionary transition as an escape from difficult habitats such as deserts or stagnant waters. These hypotheses and Romer’s Gap are tested here using depth to calcic horizon in paleosols of the northern Appalachians as a p...

Four TOC-rich shale intervals spanning the Frasnian–Famennian (F–F) boundary were recovered in a drillcore (West Valley NX-1) from western New York (USA) and radiometrically dated using Re–Os. Two of the black shale intervals (WVC785 from ∼2.9 m below, and WVC754 from ∼6.4 m above the F–F boundary, respectively) yielded statistically overlapping ages with uncertainties of b1.1%. An interpolated...

Michigan's first commercial oil field was discovered at Port Huron, St. Clair County, in 1886. By 1910, 21 shallow wells had been completed in the Dundee formation at depths of about 500 to 650 feet. In 1910 the daily production from this field amounted to about 10 barrels of oil per day, all of which was used locally in the manufacture of lubricants. However, it was not until 1925 when the Sag...

Cladoxylopsida included the earliest large trees that formed critical components of globally transformative pioneering forest ecosystems in the Mid- and early Late Devonian (ca. 393-372 Ma). Well-known cladoxylopsid fossils include the up to ∼1-m-diameter sandstone casts known as Eospermatopteris from Middle Devonian strata of New York State. Cladoxylopsid trunk structure comprised a more-or-le...

Insecta s. str. (=Ectognatha), comprise the largest and most diversified group of living organisms, accounting for roughly half of the biodiversity on Earth. Understanding insect relationships and the specific time intervals for their episodes of radiation and extinction are critical to any comprehensive perspective on evolutionary events. Although some deeper nodes have been resolved congruent...

Pollen organ Telangiopsis sp., associated with but not attached to vegetative fronds, has been collected from the Upper Devonian (Famennian) Wutong Formation, Dongzhi County, Anhui Province, China. Fertile axes with terminal pollen organs are dichotomous for 2-4 times and may be proximally attached by fragmentary pinnules. Pollen organs are synangiate and borne on the top of a short stalk. Syna...

During the Devonian, Svalbard Archipelago lay at low latitudes, occupying a paleogeographic position intersection of Caledonian and Ellesmerian orogens. Provenance analysis, including detrital zircon U-Pb age studies, Devonian (ca. 420–360 Ma) strata from Andrée Land Basin, Svalbard, help reconstruct sediment sources to understand assembly three basement provinces that make up which are present...