The rise of arthropods is a decisive event in the history of life. Likely the first animals to have
established themselves on land and in the air, arthropods have pervaded nearly all …

Patterns of segmentation and tagmosis are reviewed for Chelicerata. Depending on the
outgroup, chelicerate origins are either among taxa with an anterior tagma of six somites, or …

'A book about one apocalypse–much less five–could have been a daunting read, were it not
for the wit, lyricism, and clarity that Peter Brannen brings to every page.'Ed Yong, author of I …

Eurypterids—Palaeozoic marine and freshwater arthropods commonly known as sea
scorpions—repeatedly evolved to remarkable sizes (over 0.5 m in length) and colonized …

Introduction The Early Ordovician Fezouata Shale Formation (485–475Ma, Morocco) is a
critical source of evidence for the unfolding Great Ordovician Biodiversification Event …

Mass extinctions have altered the trajectory of evolution a number of times over the
Phanerozoic. During these periods of biotic upheaval a different selective regime appears to …

Trilobite malformations are often ascribed to failed predation and represent key evidence for
Paleozoic arthropod predator–prey systems. A large number of malformed trilobites are …

Abstract The 'Great Ordovician Biodiversification Event'represents the rapid diversification of
marine organisms during the Middle Ordovician. As the initial stage of the 'Great Ordovician …

Pterygotid eurypterids include some of the largest aquatic arthropods in the fossil record and
are known from middle Silurian to Middle Devonian deposits across the globe. These forms …

Megalograptidae and Mixopteridae with elongate, spinose prosomal appendages are
unique early Palaeozoic sea scorpions (Eurypterida). These features were presumably used …