The Preface to Darwin’s <Emphasis Type="Italic">Origin of Species</Emphasis>: The Curious History of the “Historical Sketch” *

Almost any modern reader’s first encounter with Darwin’s writing is likely to be the “Historical Sketch,” inserted by Darwin as a preface to an early edition of the Origin of Species, and having since then appeared as the preface to every edition after the second English edition. The Sketch was intended by him to serve as a short “history of opinion” on the species question before he presented his own theory in the Origin proper. But the provenance of the “Historical Sketch” is somewhat obscure. Some things are known about its production, such as when it first appeared and what changes were made to it between its first appearance in 1860 and its final form, for the fourth English edition, in 1866. But how it evolved in Darwin’s mind, why he wrote it at all, and what he thought he was accomplishing by prefacing it to the Origin remain questions that have not been carefully addressed in the scholarly literature on Darwin. I attempt to show that Darwin’s various statements about the “Historical Sketch,” made primarily to several of his correspondents between 1856 and 1860, are somewhat in conflict with one another, thus making problematic a satisfactory interpretation of how, when, and why the Sketch came to be. I also suggest some probable resolutions to the several difficulties. How Darwin came to settle on the title “Historical Sketch” for the Preface to the Origin is not certain, but a guess may be ventured. When he first submitted the text to Asa Gray in February 1860 he called it simply “Preface Contributed by the Author to this American Edition” (Burkhardt et al., eds., vol. 8, 1993, p. 572; the collected correspondence is hereafter cited as CCD). In fact he had thought of it as being properly called a Preface much earlier, perhaps as early as 1856, as will be seen in what follows. It came to be called “An Historical Sketch of the Recent Progress of Opinion on the Origin of Species” only in the third English edition, April 1861. This is the title it retained thereafter, with the exception of an addition to the title in the sixth English edition, “Previously to the Publication of the First Edition of this Work” (Peckham, 1959, pp. 20, 59). The word “sketch,” on the other hand was one of two words Darwin commonly used in private correspondence to refer to the book that would later become the Origin, the other word being “Abstract,” and both signifying that Darwin thought of the work as being a resume rather than a full-fledged study (e.g., letter to J.D. Hooker, May 9 1856, CCD vol. 6 p. 106; letter to Baden Powell January 18 1860, CCD vol. 8 p. 41; letter to Lyell 25 June 1858, CCD v. 7, 1991, pp. 117–8; letter to Lyell May 1856, CCD, v. 6 p. 100). The most likely source of the title “Historical Sketch” for Darwin’s Preface is Charles Lyell’s Principles of Geology in which, beginning with the third edition (1834), Lyell added titles to his chapters, calling chapters 2–4 “Historical Sketch of the Progress of Geology” (Secord, in Lyell [1997], p. xlvii; for other uses by Lyell of this expression, cf. Porter, 1976, p. 95; idem 1982, p. 38; and Lyell, 1830 [1990], p. 30). Further parallels between Lyell’s Introduction and Darwin’s “Historical Sketch” in terms of content and strategy are suggested below.     

Two new motile phototrophic consortia: “Chlorochromatium lunatum” and “Pelochromatium selenoides”

Two new phototrophic consortia, “Chlorochromatium lunatum” and “Pelochromatium selenoides”, were observed and collected in the hypolimnion of several dimictic lakes in Wisconsin and Michigan (USA). The two consortia had the same morphology but different pigment composition. The cells of the photosynthetic components of the consortia were half-moon-shaped. This morphology was used to differentiate them from the previously described motile phototrophic consortia “Chlorochromatium aggregatum” and “Pelochromatium roseum”. These phototrophic cells did not resemble any described unicellular green sulfur bacteria. The predominant pigments detected were bacteriochlorophyll d and chlorobactene for the green-colored “Clc. lunatum”, and bacteriochlorophyll e and isorenieratene for the brown-colored “Plc. selenoides”. Their pigment compositions and the presence of chlorosomes attached to the inner face of the cytoplasmic membrane in both kinds of photosynthetic cells confirmed this new half-moon-shaped morphotype as a green sulfur bacterium. Both consortia were found thriving in lakes with low concentrations of sulfide (< 60 μM), below the layers of “Clc. aggregatum” and “Plc. roseum”. The green consortia were observed in lakes where the oxic-anoxic interface was located at shallow depths (2–7 m), while the brown consortia were found at greater depths (8–16 m). The two newly described consortia were never detected together at the same depth in any lake. Received: 30 April 1997 / Accepted: 17 January 1998     

Microhabitat segregation and cannibalism in an endangered freshwater isopod, Thermosphaeroma thermophilum

Intraspecific microhabitat segregation is expected to arise when there are age- or sex-specific differences in predation risk. The degree to which conspecific predation (cannibalism) can generate this risk, however, is poorly understood. In this paper, we examine microhabitat use, cannibalism, and individual responses to the presence of conspecifics in Thermosphaeroma thermophilum, an endangered isopod crustacean species that is endemic to a single, thermal spring in Socorro, N.M. USA. In samples from the natural habitat, juveniles (mancas) were found mainly on vegetation, whereas adults were found predominantly on bottom sediments. Females were found on vegetation more often than males. In laboratory containers without refuges, males cannibalized females, males and females cannibalized mancas, and mancas cannibalized each other, even in the presence of alternative food. When placed in containers provided with refuges, mancas actively avoided adults. We suggest, therefore, that cannibalism in T. thermophilum generates age-, size-, and sex-specific predation risks which are responsible for microhabitat segregation between mancas and adults, and between males and females. Since interspecific predation in the spring is negligible, cannibalism appears to play a significant role in population regulation and behavioral evolution in this species. We recommend, given the current “endangered” status of this species, that microhabitat heterogeneity be maintained in its native spring because it provides refuges from cannibalism and may support a larger and more viable natural population. Received: 28 June 1996 / Accepted: 24 February 1997     

From “Lists of Traits” to “Open-Mindedness”: Emerging Issues in Cultural Competence Education

The incorporation of “culture” into U.S. biomedicine has been increasing at a rapid pace over the last several decades. Advocates for “cultural competence” point to changing patient demographics and growing health disparities as they call for improved educational efforts that train health providers to care for patients from a variety of backgrounds. Medical anthropologists have long been critical of the approach to “culture” that emerges in cultural competence efforts, identifying an essentialized, static notion of culture that is conflated with racial and ethnic categories and seen to exist primarily among exotic “Others.” With this approach, culture can become a “list of traits” associated with various racial and ethnic groups that must be mastered by health providers and applied to patients as necessary. This article uses an ethnographic examination of cultural competence training to highlight recent efforts to develop more nuanced approaches to teaching culture. I argue that much of contemporary cultural competence education has rejected the “list of traits” approach and instead aims to produce a new kind of health provider who is “open-minded,” willing to learn about difference, and treats each patient as an individual. This shift, however, can ultimately reinforce behavioral understandings of culture and draw attention away from the social conditions and power differentials that underlie health inequalities.     

Voiceprint identification and its application to sociological studies of wild Japanese monkeys (Macaca fuscata yakui)

Japanese monkeys often exchange the particular vocal sound, “coo,” especially when they feed or move as a group. It was considered that the “coo” sound had no positive social meaning, perhaps because the “coo” sound network and its function were hidden behind other behavioral observations. For identification of the vocalizer only from hearing the “coo” sound, three phonetic values, i.e., the “fundamental,” “duration,” and “formants,” plus other characteristics were used as indices of voiceprints. The results indicated that these were effective for identifying the vocalizer in two-thirds of the adults in the study troop which was composed of 12 adults and 16 immature members. The “coo” sound exchange network among the troop members (adults) was drawn on the basis of the voiceprint identification. The network showed three characteristics as follows: (1) matriarchs of the kin-groups frequently exchanged “coo” sounds with each other; (2) the other females exchanged “coo” sounds mostly within their own kin-groups; and (3) males seldom participated in the “coo” sound exchange. This suggests that “coo” sound exchange plays a central role for the matriarch of kin-groups in binding each kin-group and, ultimately, in binding all members together into an organized troop.     

Sangiran 5,(“Pithecanthropus dubius”), homo erectus, “Meganthropus,” orPongo?

There are now eleven known mandibular remains from the Lower and Middle Pleistocene of Java, all but one being from the Sangiran site. All of these have been assigned toHomo erectus by most workers, while others have suggested as many as four different hominoid taxa. The author finds that the jaws cannot be a homogeneous sample. Morphologically, they are a mixture of undoubtedH. erectus, “H. meganthropus,” and possibly a pongid. If the jaws are allH. erectus then they have a sexual dimorphism exceeding that of modern gorillas. The case of“Pithecanthropus dubius” (Sangiran 5) is even less certain; even its hominid status is disputed. If it is indeedHomo it must be placed with the other“H. meganthropus” specimens. Its size and morphology are well beyond the known range anyH. erectus.     

Life and death near a windy oasis

We propose a simple experiment to study delocalization and extinction in inhomogeneous biological systems. The nonlinear steady state for, say, a bacteria colony living on and near a patch of nutrient or favorable illumination (“oasis”) in the presence of a drift term (“wind”) is computed. The bacteria, described by a simple generalization of the Fisher equation, diffuse, divide A→A + A, die A→ 0, and annihilate A + A→ 0. At high wind velocities all bacteria are blown into an unfavorable region (“desert”), and the colony dies out. At low velocity a steady state concentration survives near the oasis. In between these two regimes there is a critical velocity at which bacteria first survive. If the “desert” supports a small nonzero population, this extinction transition is replaced by a delocalization transition with increasing velocity. Predictions for the behavior as a function of wind velocity are made for one and two dimensions. Received: 3 August 1998 / Revised version: 17 July 1999 / Published online: 4 July 2000     

Lagomorphs from the Miocene of Sandelzhausen (southern Germany)

Three genera of lagomorphs, Prolagus, Lagopsis, and “Amphilagus,” were identified during a revision of the lagomorph material from Sandelzhausen (MN5, Early/Middle Miocene boundary, southern Germany). Evidence of two morphological and dimensional classes were observed at some tooth positions in Prolagus (some p3 show an unmistakable P. oeningensis morphology, others closely resemble P. crusafonti), but not at other tooth positions (e.g., M1–2). Insufficient data from Sandelzhausen precludes identification of two different species of Prolagus from this locality, and to define the characteristics of the possible P. crusafonti-like species. Thus, all Prolagus specimens have been classified as P. aff. oeningensis. The genus Lagopsis is represented by L. cf. penai, whose presence is compatible with a MN5 age. The relative abundance of Lagopsis to Prolagus may indicate relatively cool and wet palaeoclimatic conditions. The largest primitive lagomorph species from continental Europe is present at Sandelzhausen. Morphological and dimensional comparisons with other European primitive lagomorphs exclude any affinity with the genera Eurolagus and Titanomys and with the species included in “Amphilagus ulmensis”. Some common features with “Amphilagus antiquus” were observed, although they are not sufficient for the attribution to this taxon. Until there is a general revision of European primitive lagomorphs, the Sandelzhausen giant lagomorph is classified as “Amphilagus” sp. Its origins, whether from evolution within Europe or migration from Asia, remain unknown.      

Recognition of sex in the acoustic communication of the grasshopper Chorthippus biguttulus (Orthoptera, Acrididae)

Many gomphocerine grasshoppers communicate acoustically: a male's calling song is answered by a female which is approached phonotactically by the male. Signals and recognition mechanisms were investigated in Chorthippus biguttulus with regard to the cues which allow sex discrimination. (1) The stridulatory files on the hindfemur of both sexes are homologous in that they are derived from the same row of bristles, but convergent with respect to the “pegs”. In males the pegs are derived from the bristles, and in females from the wall of the bristle's cup. (2) Male and female songs are generated by similar, probably homologous motor programs, but differ in the duration, intensity, “gappyness” of syllables, risetime of pulses, and the frequency spectra. The hindleg co-ordination during stridulation and the resulting temporal song patterns are less variable in males than in females. (3) For both sexes, recognition of a mate's signal depends on species-specific syllable structure. For males it is essential that the female syllables consist of distinct short pulses, whereas females reject “gappy” syllables. Males strongly prefer “ramped” pulses, females respond to syllables irrespective of steeply or slowly rising ramps. Males react only to the low-frequency component, whereas females prefer spectra containing both, low and high frequency components. Accepted: 20 November 1996     

Dynamic role of “illite-like” clay minerals in temperate soils: facts and hypotheses

Analysis of new data and reinterpretation of published information for clay minerals found in temperate climate soil profiles indicates that there is often a gradient of “illite-like” clay minerals with depth. We used the term “illite-like” because these observations are based on X-Ray Diffractogram patterns and not on layer charge measurements which allow to define properly illite. It appears that “illite-like” layers are concentrated in the upper, organic - rich portion of the soil profile both under grassland and forest vegetation. “Illite-like” layer quantity seems directly related to soil potassium status. Indeed, intensive agriculture practises without potassium fertilization reduce “illite-like” content in surface soils, whereas several years of potassic fertilization without plant growth can increase “illite-like” content. The potassic soil clay mineral, illite, is particularly important in that it can be the major source of readily available potassium for plants. Spatial and temporal dynamics of clay minerals should be related to the potassium cycle. We propose that the frequently observed general trend of increasing exchangeable potassium in the top soil can be correlated with an increase in “illite-like” in the clays and that the decrease of potassium caused by intensive agricultural practices leads to “illite-like” layer destabilization. This vision of “illite-like” layer as a potassium reservoir refueled by plants and emptied by intensive cropping renews the concept of potassium availability and indicates a need to be discussed as well in natural ecosystems as in cultivated ecosystems.     

Relationships among three Japanese <Emphasis Type="Italic">Laetiporus</Emphasis> taxa based on phylogenetic analysis and incompatibility tests

Relationships among three Japanese Laetiporus taxa (“L. sulphureus var. sulphureus” auct. jap., L. sulphureus var. miniatus, and L. versisporus) were assessed with phylogenetic analysis and incompatibility tests. Gene phylogenies inferred from the internal transcribed spacer region of nuclear ribosomal DNA, elongation factor 1α, and β-tubulin gene regions suggested that Japanese Laetiporus was divided into four groups: the yellow pore form of L. sulphureus var. miniatus, the white pore form of L. sulphureus var. miniatus, and two “L. sulphureus var. sulphureus”/ L. versisporus groups. A morphologically distinct species, Laetiporus versisporus, sharing a clade with “L. sulphureus var. sulphureus” auct. jap., was proved to be an anamorphic form of “L. sulphureus var. sulphureus” auct. jap. The “sulphureus/versisporus” isolates showed two divergent sequence types in each region. Some isolates had intraindividual polymorphism assigned to both sequence types. This finding suggests that speciation via hybridization is ongoing in the “sulphureus/versisporus” group. Single spore isolates from the “sulphureus/versisporus” group, white pore group, and yellow pore group were incompatible with each other. Our results provided strong support for the new recognition of three Laetiporus taxa in Japan.     

A global survey of haplotype frequencies and linkage disequilibrium at the DRD2 locus

A four-site haplotype system at the dopamine D2 receptor locus (DRD2) has been studied in a global sample of 28 distinct populations. The haplotype system spans about 25 kb, encompassing the coding region of the gene. The four individual markers include three TaqI restriction site polymorphisms (RSPs) – TaqI “A”, “B”, and “D” sites – and one dinucleotide short tandem repeat polymorphism (STRP). All four of the marker systems are polymorphic in all regions of the world and in most individual populations. The haplotype system shows the highest average heterozygosity in Africa, a slightly lower average heterozygosity in Europe, and the lowest average heterozygosities in East Asia and the Americas. Across all populations, 20 of the 48 possible haplotypes reached a frequency of at least 5% in at least one population sample. However, no single population had more than six haplotypes reaching that frequency. In general, African populations had more haplotypes present in each population and more haplotypes occurring at a frequency of at least 5% in that population. Permutation tests for significance of overall disequilibrium (all sites considered simultaneously) were highly significant (P<0.001) in all 28 populations. Except for three African samples, the pairwise disequilibrium between the outermost RSP markers, TaqI “B” and “A”, was highly significant with D’ values greater than 0.8; in two of those exceptions the RSP marker was not polymorphic. Except for those same two African populations, the 16-repeat allele at the STRP also showed highly significant disequilibrium with the TaqI “B” site in all populations, with D’ values usually greater than 0.7. Only four haplotypes account for more than 70% of all chromosomes in virtually all non-African populations, and two of those haplotypes account for more than 70% of all chromosomes in most East Asian and Amerindian populations. A new measure of the amount of overall disequilibrium shows least disequilibrium in African populations, somewhat more in European populations, and the greatest amount in East Asian and Amerindian populations. This pattern seems best explained by random genetic drift with low levels of recombination, a low mutation rate at the STRP, and essentially no recurrent mutation at the RSP sites, all in conjunction with an “Out of Africa” model for recent human evolution. Received: 14 January 1998 / Accepted 19 March 1998     

Genetic control of aluminium tolerance in rye (Secale cereale L.)

 Aluminium (Al) tolerance in roots of two cultivars (“Ailés” and “JNK”) and two inbred lines (“Riodeva” and “Pool”) of rye was studied using intact roots immersed in a nutrient solution at a controlled pH and temperature. Both the cultivars and the inbred lines analysed showed high Al tolerance, this character being under multigenic control. The inbred line “Riodeva” was sensitive (non-telerant) at a concentration of 150 μM, whereas the “Ailes” cultivar showed the highest level of Al tolerance at this concentration. The segregation of aluminium-tolerance genes and several isozyme loci in different F₁s, F₂s and backcrosses between plants of “Ailés” and “Riodeva” were also studied. The segregation ratios obtained for aluminium tolerance in the F₂s analysed were 3 : 1 and 15 : 1 (tolerant : non-tolerant) while in backcrosses they were 1 : 1 and 3 : 1. These results indicated that Al tolerance is controlled by, at least, two major dominant and independent loci in rye (Alt1 and Alt3). Linkage analyses carried out between Al-tolerance genes and several isozyme loci revealed that the Alt1 locus was linked to the aconitase-1 (Aco1), nicotinamide adenine dinucleotide dehydrogenase-2 (Ndh2), esterase-6 (Est6) and esterase-8 (Est8) loci, located on chromosome arm 6RL. The order obtained was Alt1-Aco1-Ndh2-Est6-Est8. The Alt3 locus was not linked to the Lap1, Aco1 and Ndh2 loci, located on chromosome arms, 6RS, 6RL and 6RL respectively. Therefore, the Alt3 locus is probably on a different chromosome. Received: 18 March 1997 / Accepted: 21 March 1997     

Art in global context: An evolutionary/functionalist perspective for the 21<Superscript>st</Superscript> century

Regarding the arts as something peopledo — as behaviors, rather than the residue or artifacts of behavior — makes possible a theoretical grounding about their nature and importance, an endeavor that current anthropology of art has largely abandoned. A reconsideration of the suspect and largely discarded terms “functionalism” and “evolutionism” is presented in light of current evolutionary thinking. It is suggested that a contemporary reformulation of these concepts, illustrated by the author's Darwinian or “adaptationist” perspective on art, supports aims and claims of current anthropology of art, and contributes new focus and direction to its endeavors.     

Neuronal control of behavioral plasticity: the prepacemaker nucleus of weakly electric gymnotiform fish

 Gymnotiform fish of the genera Apteronotus and Eigenmannia provide an excellent vertebrate model system to study neural mechanisms controlling behavioral plasticity. These teleosts generate, by means of an electric organ, quasi-sinusoidal discharges of extremely stable frequency and waveform. Modulations consisting of transient rises in discharge frequency are produced during social encounters, and play an important role in communication. These so-called “chirps” exhibit a remarkable sexual dimorphism, as well as an enormous seasonal and individual variability. Chirping behavior is controlled by a subset of neurons in the complex of the central posterior/prepacemaker nucleus in the diencephalon. It is hypothesized that the plasticity in the performance of chirping behavior is, at least in part, governed by two mechanisms: first, by seasonally induced structural changes in dendritic morphology of neurons of the prepacemaker nucleus, thus leading to pronounced alterations in excitatory input. Second, by androgen-controlled changes in the innervation pattern of the prepacemaker nucleus by fibers expressing the neuropeptide substance P. In addition to these two dynamic processes, cells are generated continuously and at high number in the central posterior/prepacemaker nucleus during adulthood. This phenomenon may provide the basis for a “refreshment”, thus facilitating possible changes in the underlying neural network. Accepted: 17 September 1990     

The dynamic behavior of phycobilisome movement during light state transitions in cyanobacterium <Emphasis Type="Italic">Synechocystis</Emphasis> PCC6803

Light state transition is a physiological function of oxygenic organisms to balance the excitation of photosystem II (PSII) and photosystem I (PSI), hence a prerequisite of oxygen-evolving photosynthesis. For cyanobacteria, phycobilisome (PBS) movement during light state transition has long been expected, but never observed. Here the dynamic behavior of PBS movement during state transition in cyanobacterium Synechocystis PCC6803 is experimentally detected via time-dependent fluorescence fluctuation. Under continuous excitation of PBSs in the intact cells, time-dependent fluorescence fluctuations resemble “damped oscillation” mode, which indicates dynamic searching of a PBS in an “overcorrection” manner for the “balance” position where PSII and PSI are excited equally. Based on the parallel model, it is suggested that the “damped oscillation” fluorescence fluctuation is originated from a collective movement of all the PBSs to find the “balance” position. Based on the continuous fluorescence fluctuation during light state transition and also variety of solar spectra, it may be deduced that light state transition of oxygen-evolution organisms is a natural behavior that occurs daily rather than an artificial phenomenon at extreme light conditions in laboratory.     

Pseudomonas aeruginosa infection: Activation of B suppressor cells which affect cell cooperation in the induction phase of contact sensitivity to oxazolone in mice

Pseudomonas aeruginosa depresses contact sensitivity to oxazolone in mice by activating B suppressor cells within the lymph nodes that drain the site of sensitization. These suppressor cells affect the induction phase of the immune response by blocking the cooperation between “stimulator” macrophages and “initiator” T cells on one hand and “recruited” T cells on the other.     

Birds from the Far East in Central Europe: some side-notes to Pfeifer et al. (2007)

The “reverse migration hypothesis” as the explanation for the vagrancy of Far Eastern birds in Europe is commented on. It is concluded that, as the postulated switch of 180° along a great circle line would lead the eastern or even central Siberian birds to North America rather than to Europe, the application of the “reverse migration hypothesis” to them seems untenable (which, however, does not preclude its plausibility in case of transatlantic, southern European, or even southwestern Siberian vagrants). On the other hand, patterns of appearance of the Turdus [naumanni] superspecies (Machalska et al. 1967) suggest the relationship of the phenomenon of vagrancy to post-breeding nomadic movements and/or periodical invasions of non-migrating species.     

Edward Hitchcock’s Pre-Darwinian (1840) “Tree of Life”

The “tree of life” iconography, representing the history of life, dates from at least the latter half of the 18th century, but evolution as the mechanism providing this bifurcating history of life did not appear until the early 19th century. There was also a shift from the straight line, scala naturae view of change in nature to a more bifurcating or tree-like view. Throughout the 19th century authors presented tree-like diagrams, some regarding the Deity as the mechanism of change while others argued for evolution. Straight-line or anagenetic evolution and bifurcating or cladogenetic evolution are known in biology today, but are often misrepresented in popular culture, especially with anagenesis being confounded with scala naturae. Although well known in the mid 19th century, the geologist Edward Hitchcock has been forgotten as an early, if not the first author to publish a paleontologically based “tree of life” beginning in 1840 in the first edition of his popular general geology text Elementary Geology. At least 31 editions were published and those between 1840 and 1859 had this “paleontological chart” showing two trees, one for fossil and living plants and another for animals set within a context of geological time. Although the chart did not vary in later editions, the text explaining the chart did change to reflect newer ideas in paleontology and geology. Whereas Lamarck, Chambers, Bronn, Darwin, and Haeckel saw some form of transmutation as the mechanism that created their “trees of life,” Hitchcock, like his contemporaries Agassiz and Miller, who also produced “trees of life,” saw a deity as the agent of change. Through each edition of his book Hitchcock denounced the newer transmutationist hypotheses of Lamarck, then Chambers, and finally Darwin in an 1860 edition that no longer presented his tree-like “paleontological chart.”     

pH-Induced Molten Globule State of <Emphasis Type="Italic">Rhizopus niveus</Emphasis> Lipase is More Resistant Against Thermal and Chemical Denaturation Than Its Native State

Here, we have characterized four pH-dependent states: alkaline state, “B” (pH 9.0), native state, “N” (pH 7.4), acid-induced state, “A” (pH 2.2) and molten globule state, “MG” (pH 1.8) of Rhizopus niveus lipase (RNL) by CD, tryptophanyl fluorescence, ANS binding, DLS, and enzyme activity assay. This “MG” state lacks catalytic activity and tertiary structure but it has native-like significant secondary structure. The “R _h” of all the four states of RNL obtained from DLS study suggests that the molecular compactness of the protein increases as the pH of solution decreases. Kinetic analysis of RNL shows that it has maximum catalytic efficiency at state “B” which is 15-fold higher than state “N.” The CD and tryptophanyl fluorescence studies of RNL on GuHCl and temperature-induced unfolding reveal that the “MG” state is more stable than the other states. The DSC endotherms of RNL obtained at pH 9.0, 7.4, and 2.2 were with two transitions, while at pH 1.8 it showed only a single transition.