Optimum body size: effects of food quality and temperature,when reproductive growth rate is restricted,with examples from aphids

Most models of optimum energy partitioning predict variability in adult size, although not always explicitly. Increase in size is usually attributed to an increase in the growth rate or decline in mortality. The model presented shows that this may not always be the case. Even when mortality is kept constant in organisms with overlapping generations, a constraint on the maximum reproductive growth rate may lead, when the rate of overall growth increases, to either an increase or a decline in the optimum adult body size. It is shown that adult size could be a consequence of the differential responses of life history traits to changes in temperature and food quality. This is clearly advantageous for short lived organisms, like aphids, each generation of which only experience a very small part of the great seasonal range in conditions. This hypothesis complements Iwasa's (1991) explanation of the phenotypic plasticity observed in long lived organisms. The predictions are illustrated with empirical data from aphids. The model presented, which has been verified against a very large data set, indicates that for aphids the adult weight observed at a particular combination of temperature and food quality is that at which the population growth rate, r_m, is maximized. We conclude that predictions about adult size from models based on the partitioning of energy are more likely to apply to organisms that scramble for resources, i.e., “r” selected species. The size of organisms that contest for resources is more likely to be determined by competitive status and avoidance of natural enemies.     

Variation in the post-smolt growth pattern of wild one sea-winter salmon (Salmo salar L.), and its linkage to surface warming in the eastern North Atlantic Ocean

Variation in circulus spacing on the scales of wild Atlantic salmon is indicative of changes in body length growth rate. We analyzed scale circulus spacing during the post-smolt growth period for adult one sea-winter salmon (n = 1947) returning to Scotland over the period 1993–2011. The growth pattern of the scales was subjectively and visually categorized according to the occurrence and zonal sequence of three intercirculus spacing criteria (“Slow”, “Fast” and “Check” zones). We applied hierarchical time-series cluster analysis to the empirical circulus spacing data, followed by post hoc analysis of significant changes in growth patterns within the 20 identified clusters. Temporal changes in growth pattern frequencies showed significant correlation with sea surface temperature anomalies during the early months of the post-smolt growth season and throughout the Norwegian Sea. Since the turn of the millennium, we observed (a) a marked decrease in the occurrence of continuous Fast growth; (b) increased frequencies of fish showing an extended period of initially Slow growth; and (c) the occurrence of obvious growth Checks or hiatuses. These changes in post-smolt growth pattern were manifest also in decreases in the mean body length attained by the ocean midwinter, as sea surface temperatures have risen.     

CELL SIZE DIFFERENTIATION IN THE BLOOM-FORMING DINOFLAGELLATE GYMNODINIUM CF. NAGASAKIENSE1

Two subpopulations differing essentially by their mean cell size were observed regularly in cultures and natural samples of the naked dinoflagellate Gymnodinium cf. nagasakiense Takayama et Adachi (currently known as Gyrodinium aureolum Hulburt), a species which frequently forms red tides in North European seas. “Large” cells represented the typical forms; they were morphologically similar to cells of the closely related Japanese species G. nagasakiense, which did not form any subpopulation of reduced size. “Small” and “large” cells of G. cf. nagasakiense had the same DNA content, but the nucleus of the former appeared to be much more condensed during interphase. Each cell type was able to divide and had its own growth dynamics; therefore, any intermediary between pure populations of “small” and of “large” cells were observed in culture. The “large” form generated a “small” cell by an atypical budding-like division, whereas the “small” form gave back a “large” form, once it ceased to divide, by simple enlargement of its cell body. Factory inducing cell size differentiation are yet unclear. Neither nitrogen nor phosphorus starvation induced a significant increase in the relative proportion of “small” and budding cells. Although cell size differentiation is associated with the formation of gametes in a variety of dinoflagellates, we demonstrated that “small” cells of G. cf. nagasakiense are able to divide asexually, in contrast to gametes of most other species. The high proliferative power of “small” cells as compared with normal cells suggests that they could play a significant role during red tides of G. cf. nagasakiense; in contrast, cells of the Japanese species G. Nagasakiense could sustain high growth rates with larger cell size because this species generally blooms in waters much warmer than those found in northern Europe.     

Body weight prediction in early fossil hominids: Towards a taxon-“independent” approach

The choice of a model taxon is crucial when investigating fossil hominids that clearly do not resemble any extant species (such as Australopithecus) or show significant differences from modern human proportions (such as Homo habilis OH 62). An “interhominoid” combination is not adequate either, as scaling with body weight is strongly divergent in African apes and humans for most skeletal predictors investigated here. Therefore, in relation to a study of seven long bone dimensions, a new taxon-“independent” approach is suggested. For a given predictor, its taxonomic “independence” is restricted to the size range over which the body weight-predictor relationship for African apes and humans converges. Different predictors produce converging body weight estimates (BWEs) for different size ranges: taxon-“independent” estimates can be calculated for small- and medium-sized hominids (e. g., for weights below 50 kg) using femoral and tibial dimensions, whereas upper limb bones provide converging results for large hominids (above 50 kg). If the remains of Australopithecus afarensis really belong to one species, the relationship of male (above 60 kg) to female body weight (approximately 30 kg) does not fall within the observed range of modern hominoids. Considering Sts 14 (22 kg) to represent a small-sized Australopithecus africanus, the level of encephalization lies well above that of extant apes. If OH 62 (approximately 25 kg), with limb proportions less human-like than those of australopithecines, indeed represents Homo habilis (which has been questioned previously), an increase in relative brain size would have occurred well before full bipedality, an assumption running counter to current assumptions concerning early human evolution. © 1993 Wiley-Liss, Inc.     

The competition amongDrosophila larvae in different growth stages

1. The experiment was conducted in order to examine the influence of the difference in the growth stage of the competitors on the intraspecific competition. Drosophila melanogaster, “wild” and its mutant “ebony” were used as materials.
2. The earlier developed or older larvae have considerable advantage, such as the increase of the body weight of flies, and of the total weight of flies from one vial, and high constant emerging percentage, while the younger competitors received the opposite influence in addition to the increase of the larval-pupal duration.
3. The grand total yields (the yield of “wild” plus that of “ebony”) from one vial were almost constant even the difference in the growth stage between competitors is changed.

     

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.     

Heritability of male mandible length in the stag beetle Cyclommatus metallifer

Numerous coleopteran species express male‐specific “weapon traits” that often show size variations among males, even within a single population. Many empirical studies have demonstrated that environmental conditions during development affect absolute weapon size. However, relatively few studies in horned beetles support the hypothesis that the relationship between weapon size and body size, also referred to as a “scaling relationship” or “static allometry”, is largely determined by genetic factors. In this study, the heritability of absolute mandible length and static allometry between mandible length and body size were estimated in the stag beetle Cyclommatus metallifer. While no significant heritable variation was observed in absolute mandible length, high heritability (h² = 0.57 ± 0.25) was detected in the static allometry between mandible length and body size. This is the first report on the genetic effect on male mandible size in Lucanidae, suggesting that absolute mandible size is largely determined by environmental conditions while the static allometry between weapon size and body size is primarily determined by genetic factors.     

Influence of canopy fruit location on morphological,histochemical and biochemical changes in two oil olive cultivars

The influence of different irradiance conditions was evaluated under natural solar radiation by comparing well-exposed (in) and shaded fruit (out) in canopies of olive trees (Olea europaea L). Over a 2-year period, from 50 days after full bloom up to harvest time, “in” and “out” olive samples of two genotypes (“Frantoio Millennio” and “Coratina 5/19”) were periodically collected. Morphological, histochemical, and biochemical analysis were performed to study the changes on fruit morphometric traits, oil body accumulation, and β-glucosidase enzyme activity. Some parameters were modified by shading inside the canopy in which the proportion of incident photosynthetically active radiation intercepted by the crop was 47%. Shaded fruits developed at slow rate and were characterized by late darkgoing time, reduced size, with a tendency toward oblong shape. The rapid histochemical procedure proposed to estimate the oil body accumulation during fruit ripening showed that a reduced irradiance caused a decrease in oil body density. The canopy position influenced, in a different way, the β-glucosidase activity in relation to the fruit-ripening stage in both genotypes. These findings indicate that providing an adequate and uniform lighting of the olive canopy by careful choices of orchard management practices can be a key factor for several yield components.     

Histogenesis of the cuticle of the adult flies,Sarcophaga bullata and S. argyrostoma

Sequential patterns of cuticle deposition and “melanization” in the imaginal cuticle of Sarcophaga argyrostoma in parts of the body darkening before or after emergence are examined on a histological basis. The patterns in the cuticles examined range from a simple absence of “melanization” to a complex of histological changes involving “melanization” and deposition. Ultrastructural changes in the post-emergent cuticle of Sarcophaga bullata during the hardening and darkening process and cuticle deposition are described.     

Petite bodies of the “robust” australopithecines

The “robust” australopithecines are often depicted as having large and powerfully built bodies to match their massive masticatory apparatus, but until 1988 the sample of postcranial remains attributed with certainty to this group was very limited. Almost nothing was known about the body of the East African “robust” australopithecine because taxonomic attribution of the postcrania was so uncertain. The body of the South African “robust” australopithecine had to be reconstructed from about a dozen isolated fragments of postcrania. Now a partial skeleton is attributed with confidence to the East African “robust” group along with several isolated bones. The South African sample has more than tripled. Analyses of this vastly expanded sample reveal that a large portion of postcrania attributed to “robust” australopithecines from Swartkrans Member 1 (35%) are from extraordinarily small-bodied individuals similar in size to a modern Pygmy weighing as little as 28 kg. These small elements include parts from the forelimb, spine, and hindlimb. About 22% of these Swartkrans 1 “robust” australopithecines are about the same size as a modern human weighing about 43 kgs and about 43% are larger than this standard but less than or equal to a 54 kg modern human. Approximately the same pattern is true for the Swartkrans 2 hominids, but taxonomic attribution is less certain. All of the Member 3 specimens are similar in size to the 45 kg standard. The partial skeleton of the East African “robust” australopithecine (KNM-ER 1500) has hindlimb joints that would correspond to a modern human of 34 kgs although the actual weight may be 5 to 10 kgs greater judging from shaft robusticity and forelimb size. The largest postcranial element attributed with some certainty to the East African “robust” australopithecine group (the talus, KNM-ER 1464) is about the same overall size as a modern human of 54 kgs, although its tibial facet is slightly smaller. Although many previous studies have hinted at the possibility that “robust” australopithecines had relatively small bodies, the new fossils provide substantial evidence that these creatures ranged from quite small to only moderate in body size relative to modern humans. These were the petite-bodied vegetarian cousins of our ancestors. Sexual dimorphism in body size appears to be greater than that in modern humans, similar to that in Pan, and less than that in Gorilla or Pongo, although such comparisons are of limited value given the small samples, poorly known body proportions, time averaging, and many other problems.     

PHENOTYPIC DIVERSIFICATION ACROSS AN ENVIRONMENTAL GRADIENT: A ROLE FOR PREDATORS AND RESOURCE AVAILABILITY ON THE EVOLUTION OF LIFE HISTORIES

Changes in age/size‐specific mortality, due to such factors as predation, have potent evolutionary consequences. However, interactions with predators commonly impact prey growth rates and food availability and such indirect effects may also influence evolutionary change. We evaluated life‐history differences in Trinidadian killifish, Rivulus hartii, across a gradient in predation. Rivulus are located in (1) “high predation” sites with large piscivores, (2) “Rivulus/guppy” sites with guppies, and (3) “Rivulus‐only” sites with just Rivulus. Rivulus suffer higher mortality with large predators, and guppies may prey upon small/young Rivulus in Rivulus/guppy environments. In turn, population densities decline while growth rates increase in both localities compared to Rivulus‐only sites. To explore how the direct and indirect effects of predators and guppies influence trait diversification in Rivulus, we examined life‐history phenotypes across five rivers. High predation phenotypes exhibited a smaller size at reproduction, a greater number of eggs that were smaller, and increased reproductive allotment. Such changes are consistent with a direct response to predation. Rivulus from Rivulus/guppy sites were intermediate; they exhibited a smaller size at reproduction, increased fecundity, smaller eggs, and larger reproductive allotment than Rivulus‐only fish. These changes are consistent with models that incorporate the impacts of growth and resources.     

Allometric patterns of fetal head growth in mysticetes and odontocetes: Comparison of Balaena mysticetus and Stenella attenuata

Unlike other mammals, odontocetes and mysticetes have highly derived craniofacial bones. A growth process referred to as “telescoping” is partly responsible for this morphology. Here, we explore how changes in facial morphology during fetal growth relate to differences in telescoping between the adult odontocete Stenella attenuata and the mysticete Balaena mysticetus. We conclude that in both Stenella and Balaena head size increases allometrically. Similarly, odontocete nasal length and mysticete mouth size have strong positive allometry compared to total body length. However, the differences between odontocetes and mysticetes in telescoping are not directly associated with their fetal growth patterns. Our results suggest that cranial changes related to echolocation and feeding between odontocetes and mysticetes, respectively, begin during ontogeny before telescoping is initiated.     

Experimental nutrient enrichment of forest streams increases energy flow to predators along greener food‐web pathways

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OIL FLOWERS AND OIL BEES: FURTHER EVIDENCE FOR POLLINATOR ADAPTATION

We examined foreleg length and body size variation in two species of oil-collecting bees (Rediviva; Melittidae) in southern Africa. Oil-collecting bees harvest oil from host flowers by rubbing their forelegs against oil-secreting trichomes. Significant differences in foreleg length occur among populations of both species. Rediviva “pallidula” populations vary significantly in mean foreleg length (11.34 ± 0.42 mm to 12.67 ± 0.36 mm), but not in body length (10.59 ± 0.74 to 10.80 ± 0.64), and foreleg length and body size are not significantly correlated. Instead, foreleg variation appears to be a function of host plant spur length. Ninety-two percent of the variance in foreleg length of R. “pallidula” is explained by mean Diascia spur length. Rediviva rufocincta populations vary significantly in mean foreleg length (10.12 ± 0.70 mm to 12.34 ± 0.68 mm) and in body length (9.03 ± 0.26 mm to 10.56 ± 0.24 mm). Foreleg length scales allometrically with body size in this species as 90.5% of the variance in foreleg length can be explained as a function of body length. Body size appears to be constrained by the morphology of the oil-secreting host plant. Both bees collect floral oil with specially modified setae on the tarsi of their forelegs. The length of the disti- + mediotarsus (refered to here as “tarsus”) in relation to the entire foreleg is shorter in R. rufocincta and does not increase as rapidly with increasing foreleg length as for R. “pallidula.” These differences in variation can be attributed to differences in position of oil within the flowers of the respective host plants. Rediviva “pallidula” collects oil from Diascia species that have the oil deeply situated in narrow floral spurs of varying length, while R. rufocincta collects oil from the broadly saccate flowers of Bowkeria verticillata and B. citrina.     

Nutritional Study of Three Strains of Naegleria gruberi*

Naegleria gruberi strains cloned from amebas isolated from a Vero cell culture (“TS”), a sewer drainage ditch (“PD”), and an established laboratory line (“S”) were morphologically identical except for differences in size and flagellate transforming ability. Cultivation on a Trypticase-yeast extract-glucose medium (“TYG”) fortified with autoclaved E. coli resulted in increased cell size of 2 strains. Differences also were noted in growth rates and optimal growth temperatures. The autoclaved E. coli in TYG medium was replaceable with serum only for strains TS and PD. A basal salts medium + autoclaved E. coli supported growth of all 3 strains, but the basal salts medium + serum would not support growth of any of the strains.     

Moved to Dance: Remix,Rasa, and a New India

This article looks at Bollywood dance to explore the production of the commodified bodies of global consumer culture. It focuses on “embodiment” to examine how dominant sensibilities are altered through changes in dance training and technological innovations. I argue that analyzing the dancing body as a locus of experience and expression shifts the ground from culture as text or discourse (popular in postcolonial, poststructuralist or choreographic analysis) to embodiment of subjectivity. “Remix” is the term that describes both the new training techniques and the aesthetics of Indian dances. Since the older boundaries of high and low, classical and popular are fluid under globalization, “remix” is replacing traditional codes and aesthetic experiences associated with rasa. I draw on my fieldwork among the “background dancers” in Bollywood films to argue that as consumer culture creates the dominant mode of cultural expression in India, the only durable form of dance practice seems to be the practice of consumption.     

Reproductive strategy as a major factor determining female body size and fertility of a gregarious parasitoid

The generally known “adult size‐fitness hypothesis” (ASFH) is applied to the gregarious parasitic wasp Anaphes flavipes (Foerster, 1841) (Hymenoptera: Mymaridae). ASFH is dependent on the reproductive strategy of the mother, which means the larger females have more offspring compared to smaller females. Two main factors, the mother's body size and food quantity received during larval development, can affect the body size of the offspring. For the first time, we present a study on the relative effect of both factors on fitness of the same species, wasp A. flavipes. Our data confirmed that females of A. flavipes with larger body sizes had more offspring compared to smaller ones. At the same time, mother's body size does not seem to affect the body size of the offspring. The other studied factor, quantity of food received during larval development, can be influenced by reproductive strategy (number of parasitoids developing in one host egg), host quality or the duration of development. We found only the reproductive strategy to have a statistically significant effect on body size. We demonstrated that the variable reproductive strategy (VRS) of wasp A. flavipes causes a plasticity in body size and future number of offspring. The generally known “trade‐off” scheme (more small offspring or fewer bigger offspring) does not apply to A. flavipes, because their large females have more offspring and it is their reproductive strategy that determines body size.     

Multizooidal Budding in Parasmittina trispinosa (Johnston) (Bryozoa,Cheilostomata)

Two principally different wall types occur in the bryozoan colony: Exterior walls delimiting the super-individual, the colony, against its surroundings and interior walls dividing the body cavity of the colony thus defined into units which develop into sub-individuals, the zooids. In the gymnolaemate bryozoans generally, whether uniserial or multiserial, the longitudinal zooid walls are exterior, the transverse (proximal and distal) zooid walls interior ones. The radiating zooid rows grow apically to form “tubes” each surrounded by exterior walls but subdivided by interior (transverse) walls. The stenolaemate bryozoans show a contrasting mode of growth in which the colony swells in the distal direction to form one confluent cavity surrounded by an exterior wall but internally subdivided into zooids by interior walls. In the otherwise typical gymnolaemate Parasmittina trispinosa the growing edge is composed of a series of “giant buds” each surrounded by exterior walls on its lateral, frontal, basal and distal sides and forming an undifferentiated chamber usually 2–3 times as broad and 3 or more times as long as the final zooid. Its lumen is subdivided by interior walls into zooids 2–3, occasionally 4, in breadth. This type of zooid formation is therefore similar to the “common bud” or, better-named, “multizooidal budding” characteristic of the stenoleamates but has certainly evolved independently as a special modification of the usual gymnolaemate budding.     

Ethnographic surreality,possession and the unconscious

In the Second Manifesto of Surrealism, issued by André Breton in 1929, surrealism was described as “a total recuperation of our psychic strength by a means of none other than vertiginous descent into ourselves, systematic illumination of the hidden places and progressive darkening of the other places, a perpetual walk in the forbidden zone”. Surrealism sought to represent the unconscious and forbidden zones of the psyche, of the body, of the noumenal world within, which offered access, for surrealists, to energies and intuitions repressed by “civilized” modes of perception. For Jean Rouch, the significance of surrealism, of automatic writing and ciné‐transe, rested in the potential escape they offered from the formal constraints of conventional film and of conventional perception and observation. In his celebration of ciné‐transe, and of the technological apparatus that makes it possible, it is possible to detect his desire for a freeing‐up of the constraints of consciousness—a desire to “write with the body”, to dream, to tap the unexplored power of the unconscious in its overturning of “reality”, of system, and of convention. As a phaneroscopic “wide‐angle lens”, surreality aimed to document the scientifically unexplainable, the immense experiential overload of ritual possession. It attempted to make visible, in the movement between observation and participation and across disjunctive points of view; the crossings‐over into the unconscious world by which possessed Songhay dancers gained access to powers of phaneroscopic perception. By adopting filmic techniques which follow the surrealist practice of creating “verbal and visual collage”, in which randomly‐generated images, emerging out of a trance‐like state (of “automatic writing” or "ciné‐transe"), are juxtaposed in indeterminate and polyphonic relations with each other in an attempt to disturb or destroy patterns of perception which are confining, rationalistic, linear, or restricted to conscious phenomena, Rouch believed he could create powerful representations of the unknowable. This paper relates the phaneroscopic practice of ethnographic surrealism to psychoanalytic models of the unconscious. In a discussion of Rouch's interpretation of the Hauka spirit cult in his film Les Maîtres Fous, the paper argues that the neo‐Freudian paradigm which allowed him to depict the Sohghay's weekend Hauka rites as a parodic reversion to “savagery” (which both reversed the hierarchy of colonizer/colonized and enabled participants to experience a therapeutic release from the traumas of colonization) has been challenged by Lacanian and post‐Lacanian “re‐readings” of Freud that call into question the extent to which the unconscious can be equated with a pre‐linguistic state characterized by disjunctive “primitive” and “instinctive” energies. The surrealist longing for a rupture of the symbolic order of Western rationalism and a return to the “imaginary order” of the unconscious is confounded in the Lacanian conception of the unconscious as a zone inhabited by the “discourse of the Other”. However, the work of Gillès Deleuze and Félix Guanari [1977] provides a means of conceptualizing the unconscious in terms that avoid simplistic binary logic (phenomenon/noumenon; signifier/signified; subject/object; conscious/unconscious; civilization/savagery). The unconscious is not the “unrepresentable” Other of consciousness; it is a schizophrenic phaneron, a signifying “machine”, a transgressive producer of “group fantasy”. Rejecting both Freud's Oedipal model (the unconscious as primal imagery or “ghostly signifieds"), and the Lacanian notion of the unconscious (as a play of “empty signifiers"). Deleuze and Guattari argue that the unconscious cannot be accounted for in terms of the individual child and its entry into language any more than it can be conceived of as the domain of the primitive. On the contrary, the unconscious is constituted as “group fantasy”, as collective public memory which need not be reduced to elemental (Oedipal) signifiers: “all delirium possesses a world‐historical, political and racial content”. The schizophrenic embodies the public nature of unconscious meaning, since schizophrenia is primarily a communication disorder in which an individual never sees himself in terms of a linguistically‐generated “selfhood”, and fails to adopt the “false” identity which is offered to him in the language of the Other. Schizophrenia is characterized by a refusal to treat some meanings as superior to others, to remain within the bounds of a stable identity, or to distinguish between material (noumenal) things and actions and their (phenomenal) meanings. The schizophrenic unconscious treats all experience as signs, registering language in the same way as the body registers physical stimuli. Thus “meanings in the unconscious are simply meanings as workings of the body” [Harland 1987:174–175]. The schizophrenic as a model for the unconscious holds several implications for those interested in representing the experiential power of public rituals, for the public meanings in circulation during such rituals are material and noumenal, and are registered on the bodies of the dancers as they transgress boundaries and pass beyond consciousness. Rouch's surreality attempted to inscribe this unconscious production of public meaning as it was manifested in the movements of the ritual and in the movements of the camera‐body.     

HETEROCHRONY AND ALLOMETRY: LESSONS FROM THE WATER STRIDER GENUS LIMNOPORUS

Heterochrony and allometry both deal with evolutionary modifications of ontogenies. Although data about both morphology and age are required to identify heterochronic processes, age data are not needed to study allometry. Using a simple graphical model, we show that allometric patterns cannot be used to infer the underlying heterochronic processes. We present a case study of the water strider genus Limnoporus Stål (Heteroptera: Gerridae) to illuminate the distinct roles that allometry and heterochrony play in integrated studies of the evolution of form. Multivariate analyses reveal several evolutionary modifications of growth trajectories (changes in direction, lateral transposition, and ontogenetic scaling), which are fairly consistent with the hypothesized phylogeny of the genus. Because there is no positive correlation between instar durations and size increments, size cannot be used as a proxy for age data in studies of heterochrony. In fact, a measure of overall size itself shows a remarkable variety of heterochronic changes among the six species. Mixtures of several heterochronic processes predominate over the more unitary reflections of “pure” processes. Heterochronic changes in different branches of the phylogeny, apparently independent of size scaling, suggest considerable potential for adaptive evolution. “Local” differentiation of ontogenetic traits within small clades may be at least as important as “global” evolutionary trends in large clades and will often be missed in “global” analyses.