Why were extinct gigantic birds so small?

Authors: Deeming, D. Charles; Birchard, Geoffrey F.

Source: Avian Biology Research, Volume 1, Number 4, January 2009 , pp. 187-194(8)

Publisher: Science Reviews 2000 Ltd

Buy & download fulltext article:

Price: $29.00 plus tax (Refund Policy)

Abstract:

This review details the six lineages of large flightless birds that evolved in the Late Cretaceous, Tertiary and Quaternary periods of geological time. Estimates of mass for each type of bird suggest that maximal mass is no greater than 500kg with most species attaining only 250-300 kg or less. By contrast, non-avian Archosaurs of the Mesozoic, and many mammal species of the Tertiary, attained great size with many species reaching several tonnes. Size has been limited in flightless birds because of the strength of the eggshell and in the largest species reproduction was only possible if the smaller males incubated. That reproductive characteristics limit mass in flightless birds suggests that truly gigantic non-avian theropods could not contact incubate their eggs and had to rely on environmental sources of heat energy to drive embryonic development. If fossil evidence ever arises to support proper contact incubation in a non-avian theropod then it is predicted that it will only be from a small (<250 kg) species.

Keywords: FLIGHTLESS BIRDS; LATE CRETACEOUS; TERTIARY; QUATERNARY; NON-AVIAN THEROPOD DINOSAURS

Document Type: Research article

DOI: http://dx.doi.org/10.3184/175815508X402482

Publication date: 2009-01-01

More about this publication?

Avian Biology Research, formerly Avian & Poultry Biology Reviews, has adopted a new and exciting vision for publication of ornithological research in the 21st Century.
This vision is based on two main concepts. First, the topics published by the journal will cover all aspects of ornithology. This will provide a forum for scientists to publish their work in a journal that will have a broad appeal. Second, the scope of the journal will expand to include reports of original research, letters, perspectives, news, diary and book reviews in addition to reviews. By considering a wide range of research fields for publication, Avian Biology Research provides a forum for people working in every field of ornithology.
Editor-in-Chief: Charles Deeming, University of Lincoln, UK; US Editors: Robert Etches, Crystal Biosciences, USA: Mary Ann Ottinger, University of Maryland, USA
Editorial Board
Subscribe to this Title
ingentaconnect is not responsible for the content or availability of external websites

Why were extinct gigantic birds so small?

Buy & download fulltext article:

Tools

Key

Text size:

Useful pages