Overheated Rats, Race, and the Double Gland: Paul Kammerer, Endocrinology and the Problem of Somatic Induction

Abstract

In 1920, Eugen Steinach and Paul Kammerer reported experiments showing that exposure to high temperatures altered the structure of the gonad and produced hyper-sexuality in ''heat rats,'' presumably as a result of the increased production of sex hormones. Using SteinachÕs evidence that the gonad is a double gland with distinct sexual and generative functions, they used their findings to explain ''racial'' differences in the sexuality of indigenous tropical peoples and Europeans. The authors also reported that heat induced anatomical changes in the interstitial cells of the gonad were inherited by the heat ratsÕ descendants. Kammerer used this finding to link endocrinology to his long-standing interest in the inheritance of acquired characteristics. The heat rats supported his hypothesis that the interstitial cells of the double gland were the mechanism of somatic induction in the inheritance of acquired characteristics. The Steinach-Kammerer collaboration, KammererÕs use of SteinachÕs ''puberty gland'' to explain somatic induction, and his endocrine analysis of symbiosis reveal Paul KammererÕs late career attempt to integrate endocrinology and genetics with the political ideals of Austrian socialism. With them he developed a bioethics that challenged the growing reliance on race in eugenics and instead promoted cooperation over * I am very grateful for the help of several archivists, including competition in evolution. I relate his attempt to the controversies surrounding the interstitial cells, to the status of extra-nuclear theories of heredity, and to KammererÕs commitment to Austromarxist social reforms during the interwar period.

Transgenerational Epigenetic Inheritance: Prevalence, Mechanisms, and Implications for the Study of Heredity and Evolution

“…The Austrian Lamarckian zoologist Paul Kammerer and the pioneer endocrinologist Eugen Steinach (1920) found that exposing male rats to high temperatures led to morphological and physiolog-ical changes in their offspring and grandoffspring. They suggested that the presence of hormone-secreting interstitial cells adjacent to germ cells in the gonads facilitated hormonal interactions between them, and they claimed that heat produced a change in hormone production in interstitial cells, thus affecting germline cells and carrying hereditary consequences (see Logan 2007 for a discussion of Kammerer and Steinach's work). Although the validity of this claim and its possible interpretation in terms of epigenetic inheritance is at present unclear, the possibility that there are hormonal effects on epigenetic variation is no longer considered heresy.…”

A historical and evolutionary perspective on the biological significance of circulating DNA and extracellular vesicles

“…Weismann then started suggesting that direct environmental effects on the germ-plasm were possible, but that functional changes of organs could not cause a corresponding change in the germ-plasm due to the germ being physically sequestered from not only somatic cytoplasm and idioplasm (nuclear contents), but also the germcell's cytoplasm [47,50]. Furthermore, he believed that the idioplasm of the germ-cell was a substance of extreme stability, as it could absorb nourishment and grow enormously without changing its complex molecular structure.…”

“…1 Chronological summary of the key events that led to the discovery and characterization of cirNAs and EVs from 428 BC (a) to date (b). The research topics include inheritance theories (represented by triangles), Pangenesis and graft hybridization studies (diamonds), the inheritance of acquired characteristics (chevron), genetic material and inheritance (squares), soma-to-germline information transfer (crosses), metabolic DNA (circles), EVs (half circles), cirDNA (stars), the bystander effect (rectangles), mobile protein complexes (arrow), and cancer progression and/or metastasis (plus) (direct or parallel induction) [50]. As mentioned in ''August Weismann: the argument against IAC through introducing the Weismann barrier'', Weismann believed that these environmental effects would, in any case, only influence germ-plasm growth rate or induce changes in an entire species, effectively refuting the idea that adaptive traits could be inherited by an individual.…”

“…Dias and Ressler [55] showed altered behaviour and neuro-anatomy in the offspring of parents exposed to trauma in the form of odor fear conditioning. Mice were exposed to aromatic acetophenone to activate a known odorant receptor, Olfr151, and subsequently, conceived F1 and F2 generations were then [50] screened for behavioural sensitivity to the acetophenone odor. The resulting behavioral sensitivity was found to be complemented by enhanced neuroanatomical representation of the Olfr151 pathway and CpG hypomethylation was detected in the Olfr151 gene of the F0 males and F1 generation.…”

Synthesis and separation in the history of “nature” and “nurture”

“…As late as 1924, in lectures given in Baltimore, Johns Hopkins geneticist H. S. Jennings reviewed much of the empirical evidence supporting the inheritance of acquired characteristics. He focused on the research of the Austrian zoologist, Paul Kammerer (Gliboff, 2006;Logan, 2007). Noting how controversial the notion had become by that time, Jennings also reviewed the criticisms directed at Kammerer's work.…”