Some effects of external conditions upon the white mouse

Abstract

T h e production of definite modifications in the structure, color or size of animals or plants by artificial changes in the conditions of life has been successfully accomplished over and over again by a large number of investigators. I need only allude to such classical instances as the experiments of Dorfmeister, Weismann and others on butterflies, Schmankewitsch on Artemia, Cunningham on flounders, Naegeli and Bonnier on Alpine plants, or to the more recent work of Tower' upon beetles and Beebea upon birds. T h e fact that such considerable modifications may be produced within the lifetime of an individual by physical or chemical means is in itself interesting if regarded simply as an illustration of the plasticity displayed by many organisms. But when we push our inquiry beyond the merely descriptive plane, we are brought face to face with some of the most fundamental problems of biology. Are these modifications adaptive in their character ? Do they in any instance correspond to the features which distinguish one natural species or geographical variety from one another ? And finally, do such artificially produced modifications reappear in offspring which have not themselves been subjected to the conditions of the experiment? These are some of the questions which demand an answer from the investigator. They are not so simple and easy of solution as may appear on the surface: the first 1 An Investigation of Evolution in Chrysomelid Beetles of the Genus Leptinotarsa. Carnegie *Geographic Variations in Birds, with Special Reference to the Effects of Humidity. Zoologica: Institution, 1906, pp. 320, pl. 30.

Lability of Tail Length of the White-Footed Mouse, Peromyscus leucopus noveboracensis

“…As first noted by Sumner (1909) in white mice and verified by several other authors, the temperature-induced differences of tail length reflect changes of lengths of vertebrae, not changes of the number of vertebrae. Barnett (1965) presented evidence of slight decreases in numbers of vertebrae in lab strains of Mas, but the major effect of temperature in his studies was also on the length of the vertebrae.…”

“…The effect of environmental temperature on the tail length of rodents was first investigated by Sumner (1909). He demonstrated that white mice (Mus musculus) raised at warmer temperatures had longer tails than did those raised at cooler temperatures.…”

Allen's Rule Revisited: Temperature Influences Bone Elongation During a Critical Period of Postnatal Development

“…The temperatures were selected based on published literature (Sumner, 1909;Sundstroem, 1922;Ogle, 1934;Harrison et al, 1959;Barnett and Scott, 1963;Al-Hilli and Wright, 1983), and were confirmed to induce differential extremity growth in a pilot study. The cold and warm group cages were kept inside specially designed environmental chambers (Serrat Heating and Cooling, North Royalton, OH), and otherwise treated the same as controls.…”

“…Such growth plasticity (which may or may not carry a thermal advantage: see Scholander, 1955;Steegmann 2007) could thus be a physiological response to an environmental stressor rather than an explicit genotypic adaptation for temperature control. Sumner (1909) was the first of many biologists to report an "Allen-type effect" after rearing laboratory mice at cold and warm temperatures throughout their active growth period (Sumner, 1909). Others have confirmed this basic observation in various species, including rats (Chevillard et al, 1963;Lee et al, 1969;Riesenfeld, 1973;Steegmann, 2007), mice (Sundstroem, 1922;Ogle, 1934;Ashoub, 1958;Harland, 1960;Barnett and Scott, 1963;Harrison, 1963;Noel and Wright, 1970), rabbits (Ogle and Mills, 1933), and pigs (Weaver and Ingram, 1969).…”

Developmental response to cold stress in cranial morphology of Rattus : implications for the interpretation of climatic adaptation in fossil hominins

“…Therefore, critical testing of the alternative hypotheses must rely on an experimental approach. There is some evidence to suggest that a developmental response may be at work for the postcrania (Sumner 1909), but no similar work has been done on the cranial morphology to date. Experiments performed by one of us (A.T.S.)…”