Cladistic analysis of the Middle Jurassic ammonite radiation shows how the Aalenian-age ancestral stock, known variously as the Hammatocerataceae or Hammatoceratinae, gave rise to numerous new groups in Bajocian times. ...

In this paper we investigate the presence of chaos in the system that underlies the Phanerozoic 87Sr/86Sr isotope record of seawater carbonates by means of nonlinear time series analysis. The Fourier power spectrum estimation ...