Do exaggerated chelicerae function as weapons or genitalia in a long‐jawed spider? Functional allometric analysis yields an answer

2020 ◽  
Vol 282 (1) ◽  
pp. 66-79
Author(s):  
Anne Danielson‐François ◽  
Humayra Nikhat Sullivan
Keyword(s):  
Allometric Analysis

Cage size and flight speed of the tobacco hawkmoth Manduca sexta

1995 ◽  
Vol 198 (8) ◽  
pp. 1665-1672 ◽  
Author(s):  
R Stevenson ◽  
K Corbo ◽  
L Baca ◽  
Q Le
Keyword(s):  
Manduca Sexta ◽  
Flight Speed ◽  
Flight Behavior ◽  
Cube Root ◽  
The Third ◽  
Chamber Volume ◽  
Cage Size ◽  
Allometric Analysis ◽  
Size Limits ◽  
Chamber Size

Flight speeds and behaviors of the sphinx moth Manduca sexta were recorded in chambers of four different sizes (0.57, 8.5, 44 and 447 m3). Mean horizontal speed increased linearly with the cube root of chamber volume from 0.57 m s-1 in the smallest chamber to 3.4 m s-1 in the largest. The maximum horizontal speed observed was 5.3 m s-1 in the largest chamber. Speeds decreased linearly with the logarithm of hawkmoth proximity to the wall. In a tunnel chamber (the third largest), moths often flew in a scalloped-shaped path. At the top of the scallop, they glided for 1­5 wing beats. In the largest chamber, moths could be recorded flying at angles other than horizontal (0 °). At flight angles greater or less than 0 °, mean speed decreased linearly with angle until ±40 °. At greater angles, speeds remained between 1 and 2 m s-1. Moths also flew closer to the wall at flight angles deviating from the horizontal. An allometric analysis of the flight speeds of insects and birds suggests that M. sexta may be able to fly at 7­10 m s-1. We conclude that chamber size limits the flight speed and modifies the flight behavior of the tobacco hawkmoth.

Genetic analysis of leaf development in cotton

Development ◽  
1991 ◽  
Vol 113 (Supplement_1) ◽  
pp. 39-46 ◽  
Author(s):  
Liam Dolan ◽  
R. Scott Poethig
Keyword(s):  
Leaf Growth ◽  
Leaf Shape ◽  
Cell Lineage ◽  
Cotton Leaf ◽  
Expansion Phase ◽  
Genetic Mosaics ◽  
Developmental Age ◽  
Allometric Analysis ◽  
Marginal Region ◽  
Lineage Analysis

Leaf shape in cotton is regulated by the developmental age of the shoot and by several major genes that affect leaf lobing. The effect of these factors was investigated by allometric analysis, cell lineage analysis, and by studying the expression of the leaf shape mutation, Okra, in genetic mosaics. Allometric analysis of leaf growth suggests that leaf shape is determined during the initiation of the primordium rather than during the expansion phase of leaf growth. Clonal analysis demonstrates that both the rate and duration of cell division are fairly uniform throughout the leaf. Cells in the marginal region of the developing cotton leaf contribute more to the growth of the lamina than they do in tobacco. The Okra mutation acts early in the development of a leaf and appears to accentuate a developmental pattern that is also responsible for heteroblastic variation in leaf shape. The expression of this mutation in genetic mosaics demonstrates that its effect does not diffuse laterally within the leaf primordium.

Allometric heterochrony in the Pliocene-Pleistocene planktic foraminiferal clade Globoconella

Paleobiology ◽  
1994 ◽  
Vol 20 (1) ◽  
pp. 66-84 ◽  
Author(s):  
Kuo-Yen Wei
Keyword(s):  
Opposite Direction ◽  
Morphological Evolution ◽  
Evolutionary Stage ◽  
Allometric Growth ◽  
Displacement Mode ◽  
Ancestral Lineage ◽  
Wide Range ◽  
Allometric Analysis ◽  
Acceleration Mode ◽  
Evolutionary Stasis

Allometric analysis of the size-shape relationships in the Pliocene-Pleistocene planktic foraminiferal Globorotalia (Globoconella) puncticulata-inflata plexus reveals several heterochronic modes underlying the morphological evolution of the clade. The ancestral lineage, G. puncticulata, is a peramorphocline, showing a pre-displacement mode of heterochrony between 3.5 Ma and 3.0 Ma and an acceleration mode from 3.0 to 2.7 Ma. A different peramorphosis process, isometric giantism (hypermorphosis), in the ontogeny of the ancestral stocks of Globoconella occurred at about 3.5 Ma and gave rise to the G. inflata lineage. The descendant lineage, G. inflata, appears to have adopted a paedomorphosis trend by delaying the onset of the neanic stage in ontogeny during the period of 3.5 to 2.35 Ma, resulting in a series of transposition allometries. During the interval of 2.4 to 1.73 Ma, the allometries shifted to the opposite direction, signifying a pre-displacement trend. Evolutionary stasis marks the evolution during 1.73 to 0.25 Ma. Neoteny concluded the final evolutionary stage of the G. inflata lineage during the latest Quaternary (0.26 to 0.05 Ma). The enormous plasticity and fluctuations in morphology of G. inflata are attributed to the highly positive allometric growth during the ontogeny and the wide-range transposing allometries in the phyletic history. The major changes in heterochronic mode coincide with paleoceanographic events, suggesting that the morphological evolution in the Globoconella clade has been modulated by changes in paleoceanographic conditions.

scholarly journals Allometric analysis of a morphological anti-predator trait in geographic populations of Japanese crucian carp

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Sakie Kodama ◽  
Hiroka Fujimori ◽  
Hiroshi Hakoyama
Keyword(s):  
Crucian Carp ◽  
Major Axis ◽  
Body Depth ◽  
Piscivorous Fish ◽  
Local Selection ◽  
Gape Size ◽  
Allometric Relation ◽  
Geographic Populations ◽  
The Mean ◽  
Allometric Analysis

Abstract Costly anti-predator traits tend to be expressed only in high-predation conditions. For the cyprinid fish genus Carassius, deeper body depth is more adaptive to avoid predation by gape-limited piscivorous fish, but it raises swimming costs. It is therefore predicted that the relative body depth will decrease when the prey fish has reached a size larger than the predator gape-size. This prediction was tested by allometric analysis of the relation between body depth and standard length of triploid asexual females of the Japanese crucian carp (Carassius auratus sspp.) sampled from 13 geographic populations. The overall allometric relation was not significantly different from isometry. The estimate of the common major-axis slope was close to 1 (near-isometry). The mean relative body depth differed significantly among populations. A significant positive correlation was found with the mean annual air temperature. The geographic variation suggests that local selection pressures vary. In conclusion, the hypothesis that larger fish will have lower body depth was not supported, perhaps indicating that deep body depth in large fish is adaptive for some reason other than defense against piscivorous fish.

How much water is in the tank? An allometric analysis with 205 bromeliad species

Flora ◽  
2020 ◽  
Vol 264 ◽  
pp. 151557 ◽  
Author(s):  
Gerhard Zotz ◽  
Maxi Leja ◽  
Yonatan Aguilar-Cruz ◽  
Helena J.R. Einzmann
Keyword(s):  
Allometric Analysis

Allometry of pharmacokinetics and pharmacodynamics of the muscle relaxant metocurine in mammals

1995 ◽  
Vol 268 (1) ◽  
pp. R85-R91 ◽  
Author(s):  
G. A. Gronert ◽  
D. L. Fung ◽  
J. H. Jones ◽  
S. L. Shafer ◽  
S. V. Hildebrand ◽  
...  
Keyword(s):  
Muscle Relaxant ◽  
Bimodal Distribution ◽  
Active Species ◽  
Individual Species ◽  
Effect Compartment ◽  
Large Species ◽  
Pharmacokinetics And Pharmacodynamics ◽  
Size Dependent ◽  
Physiological Time ◽  
Allometric Analysis

We investigated the effects of body size on the pharmacokinetics and pharmacodynamics of the renally cleared muscle relaxant metocurine. We hypothesized that pharmacokinetics of the drug would change allometrically in proportion to physiological time [infinity Mb0.25, where Mb is body mass] and that pharmacodynamics would be independent of size because of the highly conserved structure of the acetylcholine receptor. Metocurine effects during general anesthesia were examined in 17 rats, 8 cats, 6 dogs, 5 pigs, 7 sheep, and 12 horses. Allometric analysis demonstrated size dependence for pharmacokinetics, which were affected by physiological time (Mb0.25). Pharmacodynamics were size independent, except for the value for effect compartment concentration associated with 50% twitch paralysis (IC50). Data from individual species had a bimodal distribution that was significant: pigs and sheep were more sensitive than other large species, and their IC50 appeared size independent. IC50 was size dependent in more active species (horse, dog, cat, rat). Although the mechanism is unknown, we speculate that this trend might relate to receptor density within the end plate. Thus pharmacokinetics changed in proportion to physiological time, and pharmacodynamics were in part size independent.

The Long Limb Bones of the StW 573 Australopithecus Skeleton from Sterkfontein Member 2: Descriptions and Proportions

2018 ◽  
Author(s):  
Jason L. Heaton ◽  
Travis Rayne Pickering ◽  
Kristian J. Carlson ◽  
Robin H. Crompton ◽  
Tea Jashashvili ◽  
...  
Keyword(s):  
Lower Limb ◽  
Homo Sapiens ◽  
Recent Common Ancestor ◽  
Limb Bones ◽  
Most Recent Common Ancestor ◽  
Climbing Ability ◽  
Early Hominin ◽  
Allometric Analysis ◽  
Two Stages ◽  
Limb Proportions

Due to its completeness, the A.L. 288-1 (Lucy) skeleton has long served as the archetypal bipedal Australopithecus. However, there remains considerable debate about its limb proportions. There are three competing, but not necessarily mutually exclusive, explanations for the high humerofemoral index of A.L. 288-1: (1) a retention of proportions from an Ardipithecus-like most recent common ancestor (MRCA); (2) indication of some degree of climbing ability; (3) allometry. Recent discoveries of other partial skeletons of Australopithecus, such as those of A. sediba (MH1 and MH2) and A. afarensis (KSD-VP-1/1 and DIK-1/1), have provided new opportunities to test hypotheses of early hominin body size and limb proportions. Yet, no early hominin is as complete (>90%), as is the 3.67 Ma Little Foot (StW 573) specimen, from Sterkfontein Member 2. Here, we provide the first descriptions of its upper and lower long limb bones, as well as a comparative context of its limb proportions. As to the latter, we found that StW 573 possesses absolutely longer limb lengths than A.L. 288-1, but both skeletons show similar limb proportions. This finding seems to argue against an allometric explanation for the limb proportions of A.L. 288-1. In fact, our multivariate allometric analysis suggests that limb lengths of Australopithecus, as represented by StW 573 and A.L. 288-1, developed along a significantly different (p < 0.001) allometric scale than that which typifies modern humans and African apes. Our analyses also suggest, as have those of others, that hominin limb evolution occurred in two stages with: (1) a modest increase in lower limb length and a concurrent shortening of the antebrachium between Ardipithecus and Australopithecus, followed by (2) considerable lengthening of the lower limb along with a decrease of both upper limb elements occurring between Australopithecus and Homo sapiens.

scholarly journals Allometric Analysis Detects Brain Size-Independent Effects of Sex and Sex Chromosome Complement on Human Cerebellar Organization

2017 ◽  
Vol 37 (21) ◽  
pp. 5221-5231 ◽  
Author(s):  
Catherine Mankiw ◽  
Min Tae M. Park ◽  
P.K. Reardon ◽  
Ari M. Fish ◽  
Liv S. Clasen ◽  
...  
Keyword(s):  
Sex Chromosome ◽  
Brain Size ◽  
Chromosome Complement ◽  
Allometric Analysis ◽  
Independent Effects
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