Effects of long-term preservation on amphibian body conditions: Implications for historical morphological research

Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China
School of Biological Sciences, University of Queensland, Brisbane, Queensland, Australia
DOI
10.7287/peerj.preprints.2930v1
Subject Areas
Zoology
Keywords
Effects, Preservation, Amphibian, Body length, Body mass, Morphological
Copyright
© 2017 Shu et al.
Licence
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
Cite this article
Shu G, Gong Y, Xie F, Wu NC, Li C. 2017. Effects of long-term preservation on amphibian body conditions: Implications for historical morphological research. PeerJ Preprints 5:e2930v1

Abstract

Measurements of historical specimens are widely applied in studies of taxonomy, systematics, and ecology, but biologists often assume that the effects of preservative chemicals on the morphology of amphibian specimens do not affect their analyses. We compared the body length and body mass of 14 live and preserved (up to 10 years) amphibian species and found that the body length and body mass of preserved specimens significantly decreased by 7.1% and 26.7%, respectively, compared to those measurements of their live counterparts. Additionally, there was greater body length (3.6%) and body mass (6.6%) shrinkage in the order Urodela than in the order Anura, but there were no significant differences in body length and body mass shrinkage between males and females. Furthermore, preservation apparently distorted the magnitude of the intersexual and interspecific differences in body length observed in the fresh specimens. When species were compared, we found that the shrinkage was proportionately greater in longer species, while the body mass of heavier individuals shrank proportionately less than that of lighter individuals. Due to the effects of preservation on amphibian morphology, we propose parsimonious conversion equations to back-calculate the original body length and body mass of study animals for researchers working with historical data because morphological data from preserved specimens may lead to incorrect biological interpretations. Therefore, researchers must correct for errors due to preservation effects that may lead to the misinterpretation of results.

Author Comment

This is a submission to PeerJ for review.

Supplemental Information

Size range of frogs measured and the difference in measurements between researchers

DOI: 10.7287/peerj.preprints.2930v1/supp-1

Range and mean values of live and preserved body length

DOI: 10.7287/peerj.preprints.2930v1/supp-2

Range and mean values of live and preserved body mass

DOI: 10.7287/peerj.preprints.2930v1/supp-3

Multiple comparisons between fresh specimens and preserved specimens

DOI: 10.7287/peerj.preprints.2930v1/supp-4

The raw data in this study

DOI: 10.7287/peerj.preprints.2930v1/supp-5

The raw data for test inter-observer bias

DOI: 10.7287/peerj.preprints.2930v1/supp-6