Divergent patterns of integration and reduced constraint in the human hip and the origins of bipedalism

Mark W. Grabowski, John D. Polk, Charles C. Roseman

Research output: Contribution to journalArticle

Abstract

When compared to other hominids-great apes including humans-the human pelvis reveals a fundamental reorganization of bony morphology comprised of multiple trait-level changes, many of which are associated with bipedal locomotion. Establishing how patterns of integration-correlations and covariances among traits-within the pelvis have evolved in concert with morphology is essential to explaining this evolutionary transition because integration may facilitate or constrain morphological evolution. Here, we show that the human hip bone has significantly lower levels of integration and constraint overall when compared to other hominids, that the focus of these changes is on traits hypothesized to play major functional roles in bipedalism, and we provide evidence that the human hip was reintegrated in a pattern distinct from other members of this group. Additionally, the evolutionary transition from a nonhuman great ape-like to human hip bone morphology was significantly easier to traverse using the human integration pattern in each comparison, which suggests hominin patterns may have evolved to facilitate this transition. Our results suggest natural selection for bipedalism broke down earlier hominid integration patterns, allowing relevant traits to respond to separate selection pressures to a greater extent than was previously possible, and reintegrated traits in a way that could have facilitated evolution along the vector specifying ancestral hominid and hominin morphological differences.

Original languageEnglish (US)
Pages (from-to)1336-1356
Number of pages21
JournalEvolution
Volume65
Issue number5
DOIs
StatePublished - May 1 2011

Fingerprint

bipedalism
hominid
Hominidae
hips
Hip
bone
pelvis
Pelvic Bones
Pongidae
functional role
locomotion
Pelvis
natural selection
bones
Genetic Selection
Locomotion
Pressure

Keywords

  • Adaptation
  • Morphological evolution
  • Pleiotropy
  • Selection-natural
  • Variation

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Genetics
  • Agricultural and Biological Sciences(all)

Cite this

Divergent patterns of integration and reduced constraint in the human hip and the origins of bipedalism. / Grabowski, Mark W.; Polk, John D.; Roseman, Charles C.

In: Evolution, Vol. 65, No. 5, 01.05.2011, p. 1336-1356.

Research output: Contribution to journalArticle

@article{40e3f8b7fc1740eda14817f7f8025ff1,
title = "Divergent patterns of integration and reduced constraint in the human hip and the origins of bipedalism",
abstract = "When compared to other hominids-great apes including humans-the human pelvis reveals a fundamental reorganization of bony morphology comprised of multiple trait-level changes, many of which are associated with bipedal locomotion. Establishing how patterns of integration-correlations and covariances among traits-within the pelvis have evolved in concert with morphology is essential to explaining this evolutionary transition because integration may facilitate or constrain morphological evolution. Here, we show that the human hip bone has significantly lower levels of integration and constraint overall when compared to other hominids, that the focus of these changes is on traits hypothesized to play major functional roles in bipedalism, and we provide evidence that the human hip was reintegrated in a pattern distinct from other members of this group. Additionally, the evolutionary transition from a nonhuman great ape-like to human hip bone morphology was significantly easier to traverse using the human integration pattern in each comparison, which suggests hominin patterns may have evolved to facilitate this transition. Our results suggest natural selection for bipedalism broke down earlier hominid integration patterns, allowing relevant traits to respond to separate selection pressures to a greater extent than was previously possible, and reintegrated traits in a way that could have facilitated evolution along the vector specifying ancestral hominid and hominin morphological differences.",
keywords = "Adaptation, Morphological evolution, Pleiotropy, Selection-natural, Variation",
author = "Grabowski, {Mark W.} and Polk, {John D.} and Roseman, {Charles C.}",
year = "2011",
month = "5",
day = "1",
doi = "10.1111/j.1558-5646.2011.01226.x",
language = "English (US)",
volume = "65",
pages = "1336--1356",
journal = "Evolution; international journal of organic evolution",
issn = "0014-3820",
publisher = "Society for the Study of Evolution",
number = "5",

}

TY - JOUR

T1 - Divergent patterns of integration and reduced constraint in the human hip and the origins of bipedalism

AU - Grabowski, Mark W.

AU - Polk, John D.

AU - Roseman, Charles C.

PY - 2011/5/1

Y1 - 2011/5/1

N2 - When compared to other hominids-great apes including humans-the human pelvis reveals a fundamental reorganization of bony morphology comprised of multiple trait-level changes, many of which are associated with bipedal locomotion. Establishing how patterns of integration-correlations and covariances among traits-within the pelvis have evolved in concert with morphology is essential to explaining this evolutionary transition because integration may facilitate or constrain morphological evolution. Here, we show that the human hip bone has significantly lower levels of integration and constraint overall when compared to other hominids, that the focus of these changes is on traits hypothesized to play major functional roles in bipedalism, and we provide evidence that the human hip was reintegrated in a pattern distinct from other members of this group. Additionally, the evolutionary transition from a nonhuman great ape-like to human hip bone morphology was significantly easier to traverse using the human integration pattern in each comparison, which suggests hominin patterns may have evolved to facilitate this transition. Our results suggest natural selection for bipedalism broke down earlier hominid integration patterns, allowing relevant traits to respond to separate selection pressures to a greater extent than was previously possible, and reintegrated traits in a way that could have facilitated evolution along the vector specifying ancestral hominid and hominin morphological differences.

AB - When compared to other hominids-great apes including humans-the human pelvis reveals a fundamental reorganization of bony morphology comprised of multiple trait-level changes, many of which are associated with bipedal locomotion. Establishing how patterns of integration-correlations and covariances among traits-within the pelvis have evolved in concert with morphology is essential to explaining this evolutionary transition because integration may facilitate or constrain morphological evolution. Here, we show that the human hip bone has significantly lower levels of integration and constraint overall when compared to other hominids, that the focus of these changes is on traits hypothesized to play major functional roles in bipedalism, and we provide evidence that the human hip was reintegrated in a pattern distinct from other members of this group. Additionally, the evolutionary transition from a nonhuman great ape-like to human hip bone morphology was significantly easier to traverse using the human integration pattern in each comparison, which suggests hominin patterns may have evolved to facilitate this transition. Our results suggest natural selection for bipedalism broke down earlier hominid integration patterns, allowing relevant traits to respond to separate selection pressures to a greater extent than was previously possible, and reintegrated traits in a way that could have facilitated evolution along the vector specifying ancestral hominid and hominin morphological differences.

KW - Adaptation

KW - Morphological evolution

KW - Pleiotropy

KW - Selection-natural

KW - Variation

UR - http://www.scopus.com/inward/record.url?scp=79955137569&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=79955137569&partnerID=8YFLogxK

U2 - 10.1111/j.1558-5646.2011.01226.x

DO - 10.1111/j.1558-5646.2011.01226.x

M3 - Article

VL - 65

SP - 1336

EP - 1356

JO - Evolution; international journal of organic evolution

JF - Evolution; international journal of organic evolution

SN - 0014-3820

IS - 5

ER -