Cargando…

Quantification of intraskeletal histovariability in Alligator mississippiensis and implications for vertebrate osteohistology

Bone microanalyses of extant vertebrates provide a necessary framework from which to form hypotheses regarding the growth and skeletochronology of extinct taxa. Here, we describe the bone microstructure and quantify the histovariability of appendicular elements and osteoderms from three juvenile Ame...

Descripción completa

Detalles Bibliográficos
Autores principales: Woodward, Holly N., Horner, John R., Farlow, James O.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: PeerJ Inc. 2014
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4060058/
https://www.ncbi.nlm.nih.gov/pubmed/24949239
http://dx.doi.org/10.7717/peerj.422
_version_ 1782321315171008512
author Woodward, Holly N.
Horner, John R.
Farlow, James O.
author_facet Woodward, Holly N.
Horner, John R.
Farlow, James O.
author_sort Woodward, Holly N.
collection PubMed
description Bone microanalyses of extant vertebrates provide a necessary framework from which to form hypotheses regarding the growth and skeletochronology of extinct taxa. Here, we describe the bone microstructure and quantify the histovariability of appendicular elements and osteoderms from three juvenile American alligators (Alligator mississippiensis) to assess growth mark and tissue organization within and amongst individuals, with the intention of validating paleohistological interpretations. Results confirm previous observations that lamellar and parallel fibered tissue organization are typical of crocodylians, and also that crocodylians are capable of forming woven tissue for brief periods. Tissue organization and growth mark count varies across individual skeletal elements and reveal that the femur, tibia, and humerus had the highest annual apposition rates in each individual. Cyclical growth mark count also varies intraskeletally, but data suggest these inconsistencies are due to differing medullary cavity expansion rates. There was no appreciable difference in either diaphyseal circumference or cyclical growth mark circumferences between left and right element pairs from an individual if diaphyses were sampled from roughly the same location. The considerable intraskeletal data obtained here provide validation for long-held paleohistology assumptions, but because medullary expansion, cyclical growth mark formation, and variable intraskeletal growth rates are skeletal features found in tetrapod taxa living or extinct, the validations presented herein should be considered during any tetrapod bone microanalysis.
format Online
Article
Text
id pubmed-4060058
institution National Center for Biotechnology Information
language English
publishDate 2014
publisher PeerJ Inc.
record_format MEDLINE/PubMed
spelling pubmed-40600582014-06-19 Quantification of intraskeletal histovariability in Alligator mississippiensis and implications for vertebrate osteohistology Woodward, Holly N. Horner, John R. Farlow, James O. PeerJ Histology Bone microanalyses of extant vertebrates provide a necessary framework from which to form hypotheses regarding the growth and skeletochronology of extinct taxa. Here, we describe the bone microstructure and quantify the histovariability of appendicular elements and osteoderms from three juvenile American alligators (Alligator mississippiensis) to assess growth mark and tissue organization within and amongst individuals, with the intention of validating paleohistological interpretations. Results confirm previous observations that lamellar and parallel fibered tissue organization are typical of crocodylians, and also that crocodylians are capable of forming woven tissue for brief periods. Tissue organization and growth mark count varies across individual skeletal elements and reveal that the femur, tibia, and humerus had the highest annual apposition rates in each individual. Cyclical growth mark count also varies intraskeletally, but data suggest these inconsistencies are due to differing medullary cavity expansion rates. There was no appreciable difference in either diaphyseal circumference or cyclical growth mark circumferences between left and right element pairs from an individual if diaphyses were sampled from roughly the same location. The considerable intraskeletal data obtained here provide validation for long-held paleohistology assumptions, but because medullary expansion, cyclical growth mark formation, and variable intraskeletal growth rates are skeletal features found in tetrapod taxa living or extinct, the validations presented herein should be considered during any tetrapod bone microanalysis. PeerJ Inc. 2014-06-03 /pmc/articles/PMC4060058/ /pubmed/24949239 http://dx.doi.org/10.7717/peerj.422 Text en © 2014 Woodward et al. http://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) , 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) and either DOI or URL of the article must be cited.
spellingShingle Histology
Woodward, Holly N.
Horner, John R.
Farlow, James O.
Quantification of intraskeletal histovariability in Alligator mississippiensis and implications for vertebrate osteohistology
title Quantification of intraskeletal histovariability in Alligator mississippiensis and implications for vertebrate osteohistology
title_full Quantification of intraskeletal histovariability in Alligator mississippiensis and implications for vertebrate osteohistology
title_fullStr Quantification of intraskeletal histovariability in Alligator mississippiensis and implications for vertebrate osteohistology
title_full_unstemmed Quantification of intraskeletal histovariability in Alligator mississippiensis and implications for vertebrate osteohistology
title_short Quantification of intraskeletal histovariability in Alligator mississippiensis and implications for vertebrate osteohistology
title_sort quantification of intraskeletal histovariability in alligator mississippiensis and implications for vertebrate osteohistology
topic Histology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4060058/
https://www.ncbi.nlm.nih.gov/pubmed/24949239
http://dx.doi.org/10.7717/peerj.422
work_keys_str_mv AT woodwardhollyn quantificationofintraskeletalhistovariabilityinalligatormississippiensisandimplicationsforvertebrateosteohistology
AT hornerjohnr quantificationofintraskeletalhistovariabilityinalligatormississippiensisandimplicationsforvertebrateosteohistology
AT farlowjameso quantificationofintraskeletalhistovariabilityinalligatormississippiensisandimplicationsforvertebrateosteohistology