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The following are previously unclassified quotes about Embryology, now classified under that heading, now classified under that heading, and under subheadings alphabetically by author and date, as a temporary intermediate step towards integrating them into my quotes pages proper.
"Thus, the energy of investigators and particularly students is diverted into the essentially fruitless 19th century activity of bending the facts of nature to support second-rate generalities of no predictive value. Though enthusiasm for Haeckel's (1900) recapitulation `law' died out, unfortunately the popularity of Von Baer's `laws' of 1828 was renewed. In order to defend the latter's descriptive statements that general characters appear before special characters as an egg develops and that the less general and finally the specific characters trail along later, we have to decide intuitively that certain characters are of `morphological significance' and others are not. When referring to vertebrates, we have to use words like blastula and gastrula in such a way as to imply that things that are vastly different from each other are really very much the same." (Ballard W.W., "Problems of Gastrulation: Real and Verbal," BioScience, Vol. 26, No. 1., January 1976, pp.36-39, p.38)
"In fact, the most obvious structural characteristics of either the eggs or the cleavage stages of a shark, a salmon, a frog, a bird, or a mammal are unique each to its own class, not generally shared. We would not consider them very much alike unless we had been taught so at a very early age. Very few vertebrates pass through a stage which can strictly be called a blastula. The embryo in its period of most active morphogenetic movements is usually called a gastrula, but as all agree this word has no morphologic meaning anymore. Each class of vertebrates (in mammals we might almost say each particular order) develops and then loses its own set of temporary structures-like the parade ground `formations of maneuver' during this period." (Ballard W.W., "Problems of Gastrulation: Real and Verbal," BioScience, Vol. 26, No. 1., January 1976, pp.36- 39, p.38)
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Created: 18 July, 2003. Updated: 8 July, 2005.