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Sex versus Gender in Sea Urchins and Leeches Two Centuries after Lamarck 1816 | OMICS International | Abstract
ISSN: 2155-9910

Journal of Marine Science: Research & Development
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Commentary

Sex versus Gender in Sea Urchins and Leeches Two Centuries after Lamarck 1816

Kutschera U*

Institute of Biology, University of Kassel, D-34132 Kassel, Germany

*Corresponding Author:
Ulrich Kutschera
Institute of Biology
University of Kassel
D-34132 Kassel, Germany
Tel: 40-561-804-4467
E-mail: kut@uni-kassel.de

Received date: October 17, 2016; Accepted date: October 28, 2016; Published date: November 01, 2016

Citation: Kutschera U (2016) Sex versus Gender in Sea Urchins and Leeches Two Centuries after Lamarck 1816. J Marine Sci Res Dev 6:210.doi:10.4172/2155-9910.1000210

Copyright: © 2016 Kutschera U. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Abstract

Bi-parental (sexual) reproduction via the fusion of egg and sperm produced by adult female/male individuals in populations of animals and plants is a key process of Life on Earth. Here, the terms “sex” (fertilization) and “gender” (role of male/female individuals as providers of gametes) are described, based on the concepts of Carolus Linnaeus (1707-1778) and Julius Sachs (1832-1897). In 1816, Jean Lamarck (1744-1829) introduced the purple sea urchin (Paracentrotus lividus) as a new species, and six decades later, Oscar Hertwig (1849-1922) used this model organism to elucidate external fertilization at the sub-cellular level. Moreover, Hertwig referred to “gender” to denote male or female P. lividus-individuals (gonochorists). Sexual reproduction and gender-roles are also outlined with reference to the fish leech (Piscicola geometra), a protandrous hermaphrodite characterized by hypodermic insemination and a gender-ration of 50:50. Finally, gender-issues in vertebrate development and evolution are addressed.

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Citations : 2494

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