A Role for Aggregation Pheromones in the Evolution of Mammallike Reptile Lactation

  title={A Role for Aggregation Pheromones in the Evolution of Mammallike Reptile Lactation},
  author={Brent M. Graves and David Duvall},
  journal={The American Naturalist},
  pages={835 - 839}
Current theory concerning the origin and evolution of lactation is modified only slightly from that proposed by Darwin in 1859 (see Long 1969). Long (1972) summarized the major phases as: (1) evolution in mammallike reptiles of a vascularized incubation area, following attainment of homeothermy; (2) preadaptive utilization of cutaneous secretions from such a richly vascularized area for adherence of eggs, or, more likely, for essential moisture; (3) evolution of the marn supium; (4) utilization… 

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This review outlines important events in the evolution of milk, and suggests studies likely to provide indirect tests of the evolutionary hypotheses discussed, including thermoregulatory, antibiotic, behavioural or nutritive functions.

Notes and Comments

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  • Biology
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  • 1994
It is hypothesized that protolacteal secretions helped protect the eggs or young from bacterial, protozoal, or fungal infection and ties the molecular evolution of a major component of the milk synthesis system to the functional modifications accompanying the evolution oflactation from preexistingsystems.

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The Mammary Gland and Its Origin During Synapsid Evolution

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  • Biology
    Journal of Mammary Gland Biology and Neoplasia
  • 2004
The mammary gland apparently derives from an ancestral apocrine-like gland that was associated with hair follicles, which is retained by monotreme mammary glands and is evident as vestigial mammary hair during early ontogenetic development of marsupials.

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  • Biology, Environmental Science
    Journal of Mammary Gland Biology and Neoplasia
  • 2004
It is proposed that mammary secretion originally evolved as a means of supplying water to eggs, and as such was essential to the evolution of endothermy among the egg-laying cynodonts that were ancestral to mammals.

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Mammalian diversity indicates that artificial selection and physiological manipulation of domestic artiodactyls has only modestly exploited the potential of mammary glands as a nutritional source for humans.

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Mammalian diversity indicates that artificial selection and physiological manipulation of domestic artiodactyls indicates that certain marsupials are specialized in terms of functional independence and temporal plasticity of mammary tissues.

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Comparative genomics and transcriptomics experiments have allowed a more in-depth analysis of the molecular evolution of lactation and confirm the ancient origin of the lactation system and illuminate the role of milk in the regulation of growth and development of the young beyond simple nutritive aspects.

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  • C. Pond
  • Biology
    Evolution; international journal of organic evolution
  • 1977
It is suggested that parental feeding may partly explain why the radiation of mammals and birds was favored by the climatic changes at the Cretaceous/Tertiary transition, which coincided with the extinction of the dinosaurs and other large reptiles.

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  • T. Case
  • Biology
    The American Naturalist
  • 1978
This paper investigates hypotheses regarding the historical evolution and adaptive significance of parental care and the condition in birds and mammals. Except at the extreme upper and lower limits


  • J. Lillegraven
  • Medicine
    Evolution; international journal of organic evolution
  • 1975
The present work is a continuation with emphasis upon reproductive aspects of the problem of the marsupial-placental dichotomy in mamma lian evolution, and focuses on the condition of the newborn in the immediate common ancestor to marsupials and placentals.

Fossil and Comparative Evidence for Possible Chemical Signaling in the Mammal-Like Reptiles

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No fossil evidence on the origin of mammae is available but the now widely accepted theory that milk glands in all mammals are derived from sweat glands is widely accepted.


  • G. Bertmar
  • Biology
    Evolution; international journal of organic evolution
  • 1981
A theory on the evolution of the VN organs from fish to mammals is presented, mainly based on comparisons of the position, gross and fine structure, and the ontogeny of the organs.

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