Synthesis,tautomerism, and antimicrobial,anti-HCV,anti-SSPE,antioxidant, and antitumor activities of arylazobenzosuberones

2-Dimethylaminomethylene-1-benzosuberone 1 was coupled with diazotized aniline derivatives to afford a series of the hitherto unreported 2-arylazo-1-benzosuberones 3a–i. The tautomeric structure and the effect of substituents on the tautomeric form (s) of the products 3a–i were discussed. Similar coupling of the enaminone 1 with diazonium salts of heterocyclic amines gave the respective fused azolotriazino-benzosuberones. Some of the newly synthesized compounds showed potent antimicrobial, anti-HCV, antioxidant, antitumor (as topoisomerase I inhibitors), and antimicrobial activities.     

Wineries,drosophila, alcohol,and Adh

Summary Previous workers (McKenzie and Parsons, 1972, 1974; McKenzie, 1974; Briscoe et al., 1975) have found anomalous distributions of species of Drosophila, of sexes of D. melanogaster, and of Adh alleles in and around wineries in Australia and Spain. Field studies in California's Sonoma Valley provide evidence that the explanations advanced for these distributions may incorrect. The anomalous distribution of species was attributed to alcohol, either as a selective agent or as a behavioral stimulus. We find a virtually identical species distribution in the absence of environmental alcohol. The anomalous sex ratio was attributedd to differential survivall of the sexes when raised on alcohol. We present crude evidence thatehe difference may simply be a behavioral response to some product of fermentation, which need not be alcohol. Finally, the allele frequency difference reported from Spain was attributed to differential adult mortality on alcohol. We do not find an allele frequency difference even when alcohol is exposed, and therefore suggest that selection is occurring in pre-adult stages.     

Isolation,assay, biosynthesis,metabolism, uptake and translocation,and function of proline in plant cells and tissues

The amino acid L-proline has been the subject of intensive research during the past ten to fifteen years. This stems from the observations that it incorporates into peptide linkage thereby serving as a precursor to peptidyl-bound L-hydroxyproline, a constituent of “extensin,” and that it accumulates when some plants are exposed to diverse biological and environmental stresses. The contents of selected papers which have been published during the last quarter of a century regarding the isolation, assay, biosynthesis, metabolism, transport and function of L-proline within various plant tissues and their cells are both interpreted and summarized in this review. Occasionally, relevant information from animal and bacterial systems concerning these topics is included. Hydroxyproline-containing proteins are not considered. L-proline was reported to be a constituent of leaves as early as the 1950’s. Since then, it and its analogues have been extracted from the organs of a variety of plants. The analogues include: methyl-hydroxylproline; 4-methylene-DL-proline; L-azetidine-2-carboxylic acid; 2,3,cis-3,4-trans-dihydroxy-L-proline; L-pipecolic acid and 4-trans-hydroxypro-line. L-proline can be both detected and quantified by colorimetric, combined fluorometric-amino acid analyzer and gas Chromatographic procedures. L-proline may be synthesized from L-glutamic acid via the following biosynthetic pathway: L-glutamic acid \(\underrightarrow {\gamma - glutamic acid kinase}\) γ-glutamyl phosphate \(\underrightarrow {\gamma - glutamyl phosphate reductase}\) γ-glutamyl semialdehyde \(\underrightarrow {spontaneous cyclization}\) Δ′-pyrroline-5-Carboxylate (P5C) \(\underrightarrow {P5C reductase}\) L-proline. Proline can also originate from L-arginine and L-ornithine. Biosynthesis from the latter compound proceeds either through the γ-glutamyl semialdehyde and pyrroline-5-carboxylate pathway or alternatively a α-keto-δ-aminovaleric and pyrroline-2-carboxylate pathway. The metabolism of L-proline most likely involves the reverse of the biosynthetic pathway with an initial prolyl dehydrogenaseor prolyl oxidasemediated conversion of L-proline to Δ′-pyrroline-5-carboxylate. The metabolism of L-proline has been demonstrated to occur in excised tissues and cell free extracts, cell suspension cultures and reproductive structures. Little is known about the mechanism by which L-proline is taken up by cultured plant cells and excised tissues. Once within the plant Lproline can be translocated through the phloem at velocities similar to those for carbon dioxide assimilates. In addition to serving as a substrate for peptidyl-bound hydroxyproline, L-proline may function as an adaptation to diverse biological and environmental stresses, a cryoprotectant, a nitrogen pool, a precursor for chlorophyll synthesis upon relief of stress, a regulator together with L-histidine of fertility and sterility and/or a substrate for respiration.     

Money,power, and mitochondria

Can we devise ways for the ultra‐rich to put their wealth to good use?

The world’s richest individuals and their wealth have recently come under the spotlight, with all those luxury yachts apparently owned by Russian oligarchs and their political friends veering to safe havens beyond the reach of sanctions; most of them vastly surpassing in value the cost of an advanced warship or the on‐off‐on saga of Elon Musk’s purchase of Twitter for a sum that exceeds the annual GDP of a mid‐sized country.Even if their riches have been acquired through legal means and provide joy and sustenance to many, how can it be justified that a small number of individuals own such vast assets, when a substantial fraction of the world’s population still lives in abject misery without even the benefit of adequate food and clean water?At this time, molecular biologists have yet to join the ranks of the ultra‐rich. But there is no reason to suppose that being a molecular biologist somehow insulates us from the greed and megalomania that seems to infect those who become billionaires on the back of their inventions and investments. The most likely playgrounds in which a hypothetical molecular biologist might acquire such riches are in biotech and via the pharmaceutical industry. Big Pharma already enjoys low public esteem—in my view somewhat unfairly because its critics rarely take into account the real cost of R&D required to develop new drugs. But it is an easy target nonetheless, not least because of its scale, which inflates the bottom line of balance sheets in ways not easily justified in the eyes of “Joe Public”. Not to mention the many drugs that allegedly do not really work. In the public mind, we are already allied with corporate greed. It is not hard to see how this could become a reality.Those who have accumulated extreme wealth in other sectors, and accrued power and influence to go with it, are viewed unfavorably by most people, even if some super‐rich individuals are admired for their creativity (Walker et al, 2021). Obscene wealth is still considered obscene, even if some of it is invested in scientific research, in the alleviation of human suffering, or in sponsorship of the arts. The fact that the ultra‐rich are able to do so seems to many like a usurpation of what is rightfully the responsibility of government, especially in democratic countries, and what do the wealthiest actually spend their money on anyway? Even if some of it is given away to charity, it is at the arbitrary whim of one or a few individuals, and not a transparent process with public accountability. Surely, it would be far better if they were all subject to a global wealth tax, the proceeds of which might support the UN, whose current annual budget (about US$ 3 billion) is mere pocket money for the world’s wealthiest persons.But how could such a scheme actually work? Although the widespread sanctioning of those who supposedly bankroll the Kremlin seems to have had some effect, the ultra‐rich invariably devise ways of circumventing legal obstacles thrown in their path. There is a widespread suspicion that economic sanctions ultimately punish ordinary people rather than wayward decision‐makers or their wealthy friends. High taxes promote tax avoidance and tax havens. Strict regulations to prevent money laundering just fuel the rise of cryptocurrencies. Laws beget loopholes.Global legislation with global implementation may look like an attractive tool, but its track record is not impressive. Consider the Kyoto/Paris process on climate change, for example, or the proposal for a 15% minimum corporate tax rate worldwide. Its effects are likely to be blunted by the floor effectively becoming the ceiling, so that most or all corporations could end up paying less and not more in taxes.What about self‐regulation? Suppose EMBO made a rule that required any individual member to donate wealth accrued from molecular biology inventions above some threshold to charitable causes or be kicked out of the organization? Would such a person care? And if EMBO had any real power to frustrate their activities, would they not just be tempted to set up a rival organization where they would be free to continue their work without such restrictions?To limit the wealth and power of individuals made rich by the capitalist market economy in which we all live, I think there is only one viable tool at our disposal, namely, the capitalist market economy itself. If we collectively boycott the products and services of companies owned by the very rich, unless they donate the bulk of their wealth to good causes of which we approve, we could eventually shift the balance in favour of better practices.It may seem a pathetically inadequate tool and would certainly require a lot of time and effort. But in the long run, it could work. There is, for example, a growing movement to use market mechanisms to support ethical and environmentally sustainable businesses. Successful companies have adopted such advocacy in their own marketing, even if it sometimes seems a cynical ploy. They would not do so unless there is public demand. All we need is to add the accumulation of obscene wealth by company owners or majority shareholders as another abuse of the system that can potentially be reined in by consumer pressure. All it would take is for concerned individuals to devise a code of practice that could be used to judge compliance.Oh well, maybe in the end, I should just take comfort in the fact that all the power of the ultra‐rich stems ultimately from mitochondria.     

Homophily,Close Friendship,and Life Satisfaction among Gay,Lesbian, Heterosexual,and Bisexual Men and Women

Friends play important roles throughout our lives by providing expressive, instrumental, and companionate support. We examined sexual orientation, gender, and age differences in the number of friends people can rely on for expressive, instrumental, and companionate support. Additionally, we examined the extent to which people relied on same-gender versus cross-gender friends for these types of support. Participants (N = 25,185) completed a survey via a popular news website. Sexual orientation differences in number of same-gender and cross-gender friends were generally small or non-existent, and satisfaction with friends was equally important to overall life satisfaction for all groups. However, the extent to which people’s friendship patterns demonstrated gender-based homophily varied by sexual orientation, gender, and age. Young adult gay and bisexual men, and to some extent bisexual women and older bisexual men, did not conform to gendered expectations that people affiliate primarily with their own gender.     

Cadmium,cobalt, chromium,and experimental myocardial infarction

In the case of experimental heart muscle infarction, the infarcted tissue of 18 pigs had a cadmium content of 0.38 μg/g dry weight and a cobalt content of 0.45 μg/g dry weight. In 25 non-infarcted pig hearts, the cadmium concentration amounted to 0.27 μg/g dry weight and the cobalt concentration to 0.37 μg/g dry weight. Thus, as far as the infarcted heart muscle tissue is concerned, there is a highly significant increase in the cadmium content (p<0.01) and a significant increase in cobalt content (p<0.05) compared to a non-infarcted heart. No differences were established with regard to chromium concentrations.     

Nucleosomes,transcription, and probability

Speaking of current measurements on single ion channel molecules, David Colquhoun wrote in 2006, “Individual molecules behave randomly, so suddenly we had to learn how to deal with stochastic processes.” Here I describe theoretical efforts to understand recent experimental observations on the chromatin structure of single gene molecules, a molecular biologist''s path toward probabilistic theories.     

Signs, communication, and language

Noting the vagueness and confusion in the literature on animal behavior with regard to the phenomenon of communication, an attempt is made to define “sign” and “communication” from the point of view of cybernetics, drawing also on Susanne Langer's philosophy of symbols. The author argues that neither communication nor language can be successfully investigated as long as the dogmatic behaviorist's taboo against goal-directed or purposive activities is maintained. In accord with recent developments in feedback theory, he shows that the cyberneticist's concept of purpose can be used quite legitimately in the scientific analysis of behavior and that it makes possible a viable classification of signs as well as the discrimination of communication from other types of interaction. In conclusion some of Hockett's “design features” of language are discussed and an attempt is made to formulate criteria for the form of communcation that should be called linguistic.     

Definitions,measurements, and classifications of stimuli,situations, and environments

A review is presented of issues relevant to the definition, measurement, and classification of stimuli, situations, and environments. Problems such as the lack of adequate definitions of concepts, error and bias in measurement procedures, confusion between measurement of a concept and measurement of its behavioral effects, and the lack of agreement among alternative measures are emphasized. It is suggested that concepts be defined in terms of objective characteristics while allowing for the study of the transactional relationship between organism and environment. The work of the ethologists in defining stimuli while studying their relationship to different organismic states and situational contexts is emphasized in this regard. Following Brunswik, it is also suggested that wherever possible there be a representative sampling of variables in natural settings. Note from the editors: From time to time, Human Ecology will publish a review article. Our first in this series is a review by a psychologist of basic definitional and conceptual problems in environmental studies.This paper was prepared while the author was a Visiting Research Fellow at the Educational Testing Service. The support of ETS and my colleagues in the Division of Psychological Studies is gratefully acknowledged. The review was also supported in part by a grant from the Rutgers University Research Council.     

Humboldt,Darwin, and population

Conclusions I have attempted to clarify some of the pathways in the development of Darwin's thinking. The foregoing examples of influence by no means include all that can be found by comparing Darwin's writings with Humboldt's. However, the above examples seem adequate to show the nature and extent of this influence. It now seems clear that Humboldt not only, as had been previously known, inspired Darwin to make a voyage of exploration, but also provided him with his basic orientation concerning how and what to observe and how to write about it. An important part of what Darwin assimilated from Humboldt was an appreciation of population analysis as a tool for assessing the state of societies and of the benefits and hardships which these societies can expect to receive from the living world around them.Darwin exhibited in his Journal of Researches a casual interest in the economic and political conditions of the countries he visited, but these considerations were much less important to him than to Humboldt. Instead, Darwin, with the assistance of Lyell's Principles of Geology, shifted from Humboldt's largely economic framework to a biological one built around the species question. This shift led Darwin away from a consideration of how the population biology of animals was related to man's economy to focus instead upon how population biology fitted into the economy of nature.Humboldt's Personal Narrative served very well as a model for Darwin's Journal of Researches, thereby helping Darwin gain scientific eminence. The Journal of Researches, like virtually all of Humboldt's writings, was a contribution to scientific orthodoxy. But Darwin had, along the way, acquired an urge to do more than just add his building blocks to the orthodox scientific edifice. He decided to rearrange those blocks of knowledge into a different structure, and for that task neither Humboldt's Personal Narrative nor any other of his works could serve as a model. Humboldt had lacked the confidence which Darwin needed that biogeography and the origin of species could be understood. Humboldt had not explored very far the possible connections between biology and geology. Nor had he provided a general synthetic account of population biology. Had he done so, he might have been more explicit about the extent of his endorsement of Malthus. But even if he had, Humboldt's strong orientation toward cooperation would probably have inhibited his recognition of the importance of competition in nature.Lyell, who had also benefited from reading Humboldt, gave Darwin insights that were lacking in Humboldt's Personal Narrative. Lyell admirably demonstrated how stratigraphy, paleontology, biogeography, and population biology could be interrelated, and his reasons for doing so were essentially the same as Darwin's. Lyell's understanding of biogeography and ecology came from the writings of Augustin-Pyramus de Candolle as much as from Humboldt's, and from the former Lyell derived an appreciation for the importance of competition and also a confidence that the mysteries of biogeography could be explained.¹¹⁷ Furthermore, Lyell's discussion of all these subjects and also of evolution in his Principles of Geology is a good synthetic argument that was the ideal model for Darwin's greatest book.Darwin, having become convinced that species change through time, was able to synthesize in his mind the contributions which he had derived from the writings of Humboldt and Lyell as they applied to the species question. When Darwin wrote his Journal of Researches there were two large gaps in his thinking about evolution that bothered him—the mechanism of evolution and the causes of extinction. It was only after reading Malthus in 1838 that he realized, as Lyell had more or less pointed out, how important was competition in nature. He now had the general outlines for his theory, and in the 1845 abridged edition of his Journal, now retitled The Voyage of the Beagle, he inserted a fuller discussion of competition in nature which showed his awareness of its importance as an ecological factor.¹¹⁸ An abridged version of this paper was presented at the meeting of the History of Science Society in Washington, D.C., on 29 December 1969.     

Synthesis,characterization, and biological activity of platinum II,III, and IV pivaloamidine complexes

Imino ligands have proven to be able to activate the trans geometry of platinum(II) complexes towards antitumor activity. These ligands, like aromatic N-donor heterocycles, have a planar shape but, different from the latter, have still an H atom on the coordinating nitrogen which can be involved in H-bond formation. Three classes of imino ligands have been extensively investigated: iminoethers (HN=C(R)OR′), ketimines (HN=CRR′), and amidines (HN=C(R)NR′R″). The promising efficacy of the platinum compounds with amidines (activity comparable to that of cisplatin for cis complexes and much greater than that of transplatin for trans complexes) prompted us to extend the investigation to amidine complexes with a bulkier organic residue (R = t-Bu). The tert-butyl group can confer greater affinity for lipophilic environments, thus potentiating the cellular uptake of the compound. In the present study we describe the synthesis and characterization of pivaloamidine complexes of platinum(II), (cis and trans-[PtCl₂(NH₃){Z-HN=C(t-Bu)NH₂}] and cis and trans-[PtCl₂{Z-HN=C(t-Bu)NH₂}₂]), platinum(III) ([Pt₂Cl₄{HN=C(t-Bu)NH}₂(NH₃)₂]), and platinum(IV) (trans-[PtCl₄(NH₃){Z-HN=C(t-Bu)NH₂}] and trans-[PtCl₄{Z-HN=C(t-Bu)NH₂}₂]). The cytotoxicity of all new Pt complexes was tested toward a panel of cultured cancer cell lines, including cisplatin and multidrug resistant variants. In addition, cellular uptake and DNA binding, perturbations of cell cycle progression, induction of apoptosis, and p53 activation were investigated for the most promising compound trans-[PtCl₂(NH₃){Z-HN=C(t-Bu)NH₂}]. Remarkably, the latter complex was able to overcome both acquired and intrinsic cisplatin resistance.     

Food, Fat, and Feathers

The annual cycle of the White-throated Sparrow, Zonotrichiaalbicollis, is reviewed with brief references to facets of nutritionaland energetic importance (1) illustrating the life of a smallbird in a varying environment, and (2) showing that certainannual events in field populations can be compared with similarmanifestations in caged individuals. Data from captives areemployed in discussions of energetic variations related to (1)food, the source of nutritive input, (2) fat, the major formof caloric storage in birds, and (3) caloric expenditure. Metabolizableenergy is partitioned by phase of the annual cycle into existenceenergy, including the costs of thermoregulation, and productiveenergy, including expenditures for nocturnal activity (Zugunruhe)and molt. Costs of vernal migration in field birds are comparedwith costs of nocturnal activity in captives to show that energeticestimates in each situation are compatible. This conclusionis supported by a metabolic estimate made for field birds thatis within 6% of the estimated metabolism of captives under similarconditions. Data and statistics from seven additional speciesof buntings are used to examine several bioenergetic principlesfor homoiotherms. (1) Minimal metabolism measured by energybalance methods is proportional to the 0.7 power of body weightbut is higher than standard or resting metabolism measured bygaseous methods. (2) Metabolized energy is inversely relatedto ambient temperature below 25°C, the estimated ad libitumcritical temperature. (3) Heat production and loss are proportionatelyhigher in summer-acclimatized birds below the ad libitum criticaltemperature due to reduced insulation. Two summary plots, relatingtemperature, metabolizable energy, and body weight are given.Directions for future research in the study of avian nutritionare suggested.     

Heterochromatin,colchicine, and karyotype

Summary Species of Chilocorus differ in chromosome number owing to centric fusion of metacentric chromosomes. The concomitant loss of arms is tolerated because in all unfused chromosomes one arm is completely heterochromatic, the other euchromatic. Under the influence of colchicine, the arms of unfused and fused chromosomes contract differentially. Unless the distribution of heterochromatin is known, karyotype analysis is destined to failure.Contribution No. 1138, Forest Entomology and Pathology Branch, Department of Forestry, Ottawa, Canada.Dedicated to Professor H. Bauer on the occasion of his sixtieth birthday.     

Pollen,ovules, and pollination in pea: Success,failure, and resilience in heat

Field pea (Pisum sativum), a major grain legume crop, is autogamous and adapted to temperate climates. The objectives of this study were to investigate effects of high temperature stress on stamen chemical composition, anther dehiscence, pollen viability, pollen interactions with pistil and ovules, and ovule growth and viability. Two cultivars (“CDC Golden” and “CDC Sage”) were exposed to 24/18°C (day/night) continually or to 35/18°C for 4 or 7 days. Heat stress altered stamen chemical composition, with lipid composition of “CDC Sage” being more stable compared with “CDC Golden.” Heat stress reduced pollen viability and the proportion of ovules that received a pollen tube. After 4 days at 35°C, pollen viability in flower buds decreased in “CDC Golden,” but not in “CDC Sage.” After 7 days, partial to full failure of anthers to dehisce resulted in subnormal pollen loads on stigmas. Although growth (ovule size) of fertilized ovules was stimulated by 35°C, heat stress tended to decrease ovule viability. Pollen appears susceptible to stress, but not many grains are needed for successful fertilization. Ovule fertilization and embryos are less susceptible to heat, but further research is warranted to link the exact degree of resilience to stress intensity.     

Valuation, appraisal, discounting, obsolescence and depreciation

Previous editions of this Journal have drawn attention to the critical role valuation plays in life cycle analysis and environmental impact assessment (see for exampleVolkwkin andKlöpffer |1|). In particular, the critical role of valuation has heen highlighed in a number of discussions on ‘valuation step’ within life cycle costing, ‘hedonic and contingency’ assessments of environmental impact and both the utility and welfare of ‘pathway’ analysis/assessment (Krkwitt, Mayerhofer, Trukenmüller andFriedrich, 1998;Powell, Pearce andCraighill, 1997;Volkwein, On in andKlöpffer, 1996 |2-4|). Focusing on the utility of market valuation, this paper examines the critique of discounting environmentalists have made in relation to property valuation, investment appraisal and the application of the principle in the income based net annual return model of land use time-horizons and the spatial configuration of building programmes-a criticism implict in ‘valuation step’, ‘hedonic, contingency’ and ‘pathway’ analysis/assessments. It examines the argument put forward regarding the link between the selection of a discount rate, the valuation of property, appraisal of investment and inter-generational downloading of costs associated with the use of land, repair, maintenance and refurbishment of buildings: the downloading of costs, seen by some, to have an adverse impact and work against the introduction of experimental designs aimed at energy saving, clean air environments.     

Control of potato cyst-nematode, Globodera rostochiensis, and root-knot nematode, Meloidogyne incognita, by organosphosphorus, carbamate, benzimidazole and other compounds

Control of potato cyst-nematode, Globodera rostochiensis, was examined on potato or tomato in pots and on potato in field plots by various chemicals incorporated into the soil at planting. The most effective nematicides were organophosphorus compounds, generally of the type O,O-diethyl O-phosphoro-thioates or O,O-diethyl phosphorodithioates, carbamates and benzimidazoles. In organic soils, the more lipophilic compounds were less effective, presumably because of sorption onto soil organic matter. Foliar sprays of chemicals, including oxamyl which is known to be translocated to roots, gave poor control of G. rostochiensis. The root-knot nematode, Meloidogyne incognita, on tomato, widely used in screening for nematicidal activity, was controlled by aldicarb or phoxim incorporated into the soil at planting, but not by benomyl or thiabendazole, in contrast to the moderate effectiveness of these latter two chemicals against G. rostochiensis.     

Geometry, thermodynamics, and protein

We derive a new continuous free energy formula for protein folding. We obtain the formula first by adding hydrophobic effect to a classical free energy formula for cavities in water. We then obtain the same formula by geometrically pursuing the structure that fits best the well-known global geometric features of native structures of globular proteins: 1. high density; 2. small surface area; 3. hydrophobic core; 4. forming domains for long polypeptide chains. Conformations of a protein are presented as an all atom CPK model where each atom is a ball B(x_i,r_i). All conformations satisfy generally defined steric conditions. For each conformation P of a globular protein, there is a closed thermodynamic system Ω_P⊃P bounded by the molecular surface M_P. Both methods derive the same free energy aV(P)+bA(P)+cW(P), where a,b,c>0, V(P), A(P), and W(P) are volume of Ω_P, area of M_P, and area of the hydrophobic surface W_P⊂M_P, which quantifies hydrophobic effect.Minimizing W(P) is sufficient to produce statistically significant native like secondary structures and hydrogen bonds in the proteins we simulated.     

The effect of malathion,diazinon, and various concentrations of zinc,copper, nickel,lead, iron,and mercury on fish

Acute and chronic toxicity tests for malathion, diazinon, copper (Cu), mercury (Hg), lead (Pb), zinc (Zn), nickel (Ni), and iron (Fe) were conducted. Mortalities ofBarilius vagra andCyprinus carpio (common carp) were variable but LC50-96 hr were similar for pesticides. AdultB. vagra seem to be more sensitive to malathion than juvenile carp. Both juvenile carp and adultB. vagra were extremely sensitive to diazinon. Long-term exposure to pesticides modified morphology and behavior. The LC50-96 values for Cu, Hg, and Pb were 0.3, 0.16, and 0.44, respectively, for smaller fish and 1.0, 0.77, and 1.33, respectively, for larger fish. Replicate LC50 values for Zn, Ni, and Fe were somewhat variable, and for these metals, the size of the fish seemed to affect response because LC50 values increased as fish size increased. Cooper, Pb, Zn, and Fe residues following exposure to sublethal concentrations of these metals for 15 d were significantly greater in whole juvenile common carp than in controls.     

Ecosystem engineering,experiment, and evolution

This paper argues that philosophers should pay more attention to the idea of ecosystem engineering and to the scientific literature surrounding it. Ecosystem engineering is a broad but clearly delimited concept that is less subject to many of the “it encompasses too much” criticisms that philosophers have directed at niche construction. The limitations placed on the idea of ecosystem engineering point the way to a narrower idea of niche construction. Moreover, experimental studies in the ecosystem engineering literature provide detailed accounts of particular empirical situations in which we cannot neglect the O term in dE/dt = g (O, E), which helps us get beyond verbal arguments and simple models purporting to show that niche construction must not be ignored as a factor in evolution. Finally, this literature demonstrates that while ecosystem engineering studies may not require us to embrace a new evolutionary process, as niche construction advocates have claimed, they do teach us that the myriad abiotic factors concealed by the abstract term ‘environment’ are often controlled in large part by organisms.