Heterochrony and Von Baer's Law in Vertebrates Analytical Essay by Nicky

Looks at the concepts of heterochrony and Von Baer's law using four species of vertebrates as examples.
# 149801 | 4,240 words | 13 sources | MLA | 2011 | US
Published on Jan 01, 2012 in Biology (Molecular and Cell) , Biology (Genetics) , Biology (Zoology)

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This paper explains that the concepts of heterochrony and Von Baer's law have provided compelling evidence as to the validity of evolution as a theory and even more importantly explains the mechanism by which evolution occurs. Next, the author relates that Von Baer's law is concerned with the morphological and therefore genetic similarities in certain species, especially in regards to embryonic development with the timing of the divergence in the developmental process amongst species; whereas, heterochrony is the differentiation of morphological aspects between two or more species based on different timing and rates for the same developmental process. The paper examines the hagfish, zebra fish, frog and pig to provide examples of various stages of embryonic development from the egg size and early cleavage, gastrulation and the development of the pharyngeal arches, urogenital systems, limb and the central and peripheral nervous systems.

Table of Contents:
Von Baer's Law
Synthesizing Heterochrony and Von Baer's Law
Egg Size and Early Cleavage
Development of the Pharyngeal Arches
Development of the Urogenital Systems
Limb Development
Development of the Central and Peripheral Nervous Systems

From the Paper:

"This statement reflects what is now typically known as Von Baer's law. It is important enough even on its surface--the fact the different embryos can be observed to develop similarly means that the observation of one species could lead to useful knowledge pertaining to a wider class of species. Furthermore, the mere existence of these morphological--and therefore genetic--commonalities in vertebrate species is easily observable evidence as to the interrelatedness of life, and more so of the closer relationships shared by more specific classes of animals (i.e vertebrates). But as exciting and compelling as these surface similarities may be, the deeper implications of Von Baer's law are far more essential.
"Von Baer did not stop with his observation that similar structures and even developmental patterns existed in all vertebrate species, but he also noted the timing of these developments and their digressions from each other. Charles Darwin, the father of evolutionary science, "recognized an evolutionary interpretation [of Von Baer's observations] of great potential...look for similarity in embryos since evidence of common ancestry is so often obscured by highly particular adult modifications.""

Sample of Sources Used:

  • Enger, Eldon; Ross, Frederick C. & Bailey, David. Concepts in Biology. New York: McGraw-Hill, 2006.
  • Gould, Stephen Jay. Ontogeny and Phylogeny. Cambridge: Harvard University Press, 1977.
  • Hunter, M. G. "Oocyte Maturation and Ovum Quality in Pigs." Reviews of Reproduction, 2000, 5, 122-30.
  • Kim, Y.J.; Jeon, Y.P. & Hyun, S.H. "Cleavage Assessment at Day 2 to Predict Blastocyst Developmental Potential in Porcine In Vitro-Fertilized Embryos." Reproduction, Fertility, and Development, 2009, 21(1), pp. 203.
  • Morton, Timothy. Ecology Without Nature. Cambridge: University of Harvard Press, 2007.

Cite this Analytical Essay:

APA Format

Heterochrony and Von Baer's Law in Vertebrates (2012, January 01) Retrieved March 03, 2024, from https://www.academon.com/analytical-essay/heterochrony-and-von-baer-law-in-vertebrates-149801/

MLA Format

"Heterochrony and Von Baer's Law in Vertebrates" 01 January 2012. Web. 03 March. 2024. <https://www.academon.com/analytical-essay/heterochrony-and-von-baer-law-in-vertebrates-149801/>