Impacts of leg loss and regeneration on body condition, growth, and development time in the wolf spider Schizocosa ocreata

2007 ◽  
Vol 85 (7) ◽  
pp. 823-831 ◽  
Author(s):  
K.M. Wrinn ◽  
G.W. Uetz
Keyword(s):  
Body Size ◽  
Body Condition ◽  
Growth And Development ◽  
Development Time ◽  
Wolf Spider ◽  
Limb Loss ◽  
Lower Body ◽  
Schizocosa Ocreata ◽  
Trade Offs ◽  
Subsequent Regeneration

Autotomy (self-amputation) of appendages and subsequent regeneration is common to many taxa. These processes are known to affect foraging abilities, growth, and development time in many taxa. However, little is known about their effects in arachnids. We addressed the effects of autotomy and regeneration on body condition, growth (size and mass), and development time (molt interval) for the wolf spider Schizocosa ocreata (Hentz, 1844) in the field and laboratory. Frequency of autotomy in the field was high (11%–19%). Field-caught individuals with missing or regenerating legs had significantly lower body size, mass, and condition. To test the effects of regeneration on size, mass, and molt interval in the laboratory, we induced autotomy of one or both forelegs. Spiders regenerating two legs had reduced molt intervals, were smaller, and weighed less than spiders that were intact or regenerating one leg. Field-caught spiders that had undergone autotomy and regeneration in the laboratory exhibited reduced size, mass, and molt interval. In contrast, laboratory-reared spiders exhibited increased molt intervals but no difference in mass after regeneration. These results reveal that limb loss via autotomy is common (but potentially costly) in S. ocreata, and that environmentally mediated trade-offs between growth and development time may occur during regeneration.

scholarly journals Dehydration resistance and tolerance in the brush-legged wolf spider (Schizocosa ocreata): a comparison of survivorship, critical body water content, and water-loss rates between sexes

2017 ◽  
Vol 95 (6) ◽  
pp. 417-423 ◽  
Author(s):  
Samantha K. Herrmann ◽  
J. Andrew Roberts
Keyword(s):  
Water Content ◽  
Water Loss ◽  
Water Mass ◽  
Critical Mass ◽  
Wolf Spider ◽  
Body Water ◽  
Lower Body ◽  
Schizocosa Ocreata ◽  
Eastern Deciduous Forests ◽  
Loss Rates

Small-bodied terrestrial animals like spiders face challenges maintaining water reserves essential for homeostasis. They may experience dry microclimates and (or) seasonal variation in water availability, so dehydration is a common stressor that may help explain movement, foraging, and other behaviors. This study examines aspects of dehydration resistance and tolerance in the brush-legged wolf spider, Schizocosa ocreata (Hentz, 1844) (Araneae: Lycosidae), commonly found in the leaf litter of eastern deciduous forests of North America. Sexes differ in morphology, physiology, reproductive strategy, and life history, likely resulting in divergent abilities to resist and tolerate dehydration. We used humidity-controlled chambers to examine relative survivorship by sex under varying humidity regimes, water-loss rates, body water content, and critical water mass. Spiders survived significantly longer in higher humidity regimes (≥50% RH). Females had significantly better survivorship overall, lower body-loss rates, and lower critical mass, though males had greater percent body water content, indicating that females have greater dehydration resistance and tolerance than males. Although sex-based differences in survival time and water-loss rates are likely an effect of relative body mass, females should be more successful than males during periods of episodic drought and are likely selected to survive later in the season while caring for offspring.

Signs of nutrition in ADHD children

2011 ◽  
Vol 26 (S2) ◽  
pp. 318-318
Author(s):  
H. Kuzelova ◽  
R. Ptacek ◽  
H. Papezova
Keyword(s):  
Growth And Development ◽  
Normal Population ◽  
Body Height ◽  
Clinical Population ◽  
Abdominal Circumference ◽  
Lower Body ◽  
Weight Changes ◽  
Children With Adhd ◽  
Adhd Children ◽  
Anthropometric Characteristics

According to current studies and clinical practice ADHD children show probable changes in growth and development, mainly in signs of nutrition. ADHD can be associated with higher predisposition to obesity, higher values of signs of nutrition, as body mass index or higher value of fat. Growth and weight changes in ADHD children are usually described in connection to stimulants use, the most common medication of the disorder. However, present research confirmed that these changes could be more typical for the disorder than for the treatment. These characteristics are considered to be directly connected with the disorder.The presented study compared anthropometric characteristics - mainly signs of nutrition - skin folds, abdominal circumference, in medicated and non-medicated ADHD boys (n = 104, age 4–16 years) with the normal non-clinical population. The results of the presented study showed significant differences between children with ADHD and those without the diagnosis. The differences found to be statistically significant (p < 0.01) being signs of nutrition (percentage of fat, abdominal circumference) and also growth suppression (lower body height). Differences between the medicated and non-medicated groups corresponded only to a lower value of body fat in the medicated children.ADHD can higher values of nutrition signs (percentage of fat, abdominal circumference, BMI, weight) in comparison to normal population. It could be caused by specific feeding customs which should be monitored in further studies.

Life history of tundra-dwelling wolf spiders (Araneae: Lycosidae) from the Yukon Territory, Canada

2012 ◽  
Vol 90 (6) ◽  
pp. 714-721 ◽  
Author(s):  
J.J. Bowden ◽  
C.M. Buddle
Keyword(s):  
Reproductive Effort ◽  
Abiotic Factors ◽  
Wolf Spider ◽  
Local Variation ◽  
Yukon Territory ◽  
The Arctic ◽  
Wolf Spiders ◽  
Female Body Size ◽  
Trade Offs ◽  
History Of

We studied populations of three tundra-dwelling wolf spider (Lycosidae) species to determine reproductive trait relationships and developmental timing in the Arctic. We collected 451 Pardosa lapponica (Thorell, 1872), 176 Pardosa sodalis Holm, 1970, and 117 Pardosa moesta Banks, 1892 during summer 2008. We used log-likelihood ratio tests and multiple linear regressions to determine the best predictors of fecundity and relative reproductive effort. Female body size best explained the variation in fecundity and body condition was the best predictor for relative reproductive effort. We tested for a trade-off between the allocation of resources to individual eggs and the number of eggs produced (fecundity) within each species using linear regression. There was variation in detectable egg size and number trade-offs among sites and these may be related to local variation in resource allocation linked to density-related biotic or abiotic factors. These findings contribute to knowledge about the fitness of arctic wolf spiders in the region of study and are particularly relevant in light of the effects that climate changes are predicted to have on the arctic fauna.

scholarly journals Enzymatic antioxidants but not baseline glucocorticoids mediate the reproduction–survival trade-off in a wild bird

2018 ◽  
Vol 285 (1892) ◽  
pp. 20182141 ◽  
Author(s):  
Stefania Casagrande ◽  
Michaela Hau
Keyword(s):  
Life History ◽  
Body Condition ◽  
Redox State ◽  
Reproductive Investment ◽  
Redox System ◽  
Reactive Oxygen Metabolites ◽  
Enzymatic Antioxidants ◽  
Trade Off ◽  
Trade Offs ◽  
Nest Provisioning

The trade-off between reproductive investment and survival is central to life-history theory, but the relative importance and the complex interactions among the physiological mechanisms mediating it are still debated. Here we experimentally tested whether baseline glucocorticoid hormones, the redox system or their interaction mediate reproductive investment–survival trade-offs in wild great tits ( Parus major ). We increased the workload of parental males by clipping three feathers on each wing, and 5 days later determined effects on baseline corticosterone concentrations (Cort), redox state (reactive oxygen metabolites, protein carbonyls, glutathione peroxidase [GPx], total non-enzymatic antioxidants), body mass, body condition, reproductive success and survival. Feather-clipping did not affect fledgling numbers, chick body condition, nest provisioning rates or survival compared with controls. However, feather-clipped males lost mass and increased both Cort and GPx concentrations. Within feather-clipped individuals, GPx increases were positively associated with reproductive investment (i.e. male nest provisioning). Furthermore, within all individuals, males that increased GPx suffered reduced survival rates. Baseline Cort increases were related to mass loss but not to redox state, nest provisioning or male survival. Our findings provide experimental evidence that changes in the redox system are associated with the trade-off between reproductive investment and survival, while baseline Cort may support this trade-off indirectly through a link with body condition. These results also emphasize that plastic changes in individuals, rather than static levels of physiological signals, may mediate life-history trade-offs.

scholarly journals Investigation on the rate of limb loss of the wolf spider, Pardosa astrigera

2013 ◽  
Vol 55 (0) ◽  
pp. 135-137
Author(s):  
Hiroyuki Iida ◽  
Katsuyuki Kohno ◽  
Mitsuyoshi Takeda
Keyword(s):  
Wolf Spider ◽  
Limb Loss ◽  
Pardosa Astrigera

The effects of overwintering and habitat type on body condition and locomotion of the wolf spider Pardosa alacris

2018 ◽  
Vol 89 ◽  
pp. 38-42 ◽  
Author(s):  
Kapilkumar Ingle ◽  
Ádám Horváth ◽  
Nikolett Gallé-Szpisjak ◽  
Levente Gellért ◽  
Enikő Csata ◽  
...  
Keyword(s):  
Body Condition ◽  
Habitat Type ◽  
Wolf Spider
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