SEARCHING BEHAVIOUR OF ADULT FEMALE COCCINELLIDAE (COLEOPTERA) ON STEM AND LEAF MODELS

1994 ◽  
Vol 126 (2) ◽  
pp. 389-399 ◽  
Author(s):  
B.D. Frazer ◽  
R.R. McGregor

AbstractBehaviour of locally occurring adult females of seven species of coccinellids was assessed on wooden dowel and paper models that mimicked branching patterns and arrangements of leaf attachments to stems. Ambient temperature and hunger of the beetles were controlled. The movements up or down the main branch of the branch models when contacted from a side branch, duration of searching, and method of leaving leaf models were recorded for 20 beetles of each species.Each species responded to the seven models with different frequencies of behaviours that reflected species-specific modifications of the taxes that lead coccinellids to the tops and terminal parts of plants. Some beetles consistently modified the pattern of responses on die models that was displayed by die species as a whole. The individual modifications could be selected for. The differences in frequencies of behaviours were judged to be sufficient to result in differences in the efficiency with which plants with different architectures were searched.

2015 ◽  
Vol 24 (1) ◽  
pp. 34-40 ◽  
Author(s):  
B. P. Heyojoo ◽  
S. Nandy

This study aims to estimate above-ground phytomass and carbon of TROF ecosystem in part of Bijnor district in Uttar Pradesh state of India using IRS P6 LISS-IV satellite image by geo-spatial approach coupled with field sampling. Chacko’s formula was referred to compute number of samples in each TROF types and the sample plot size in each stratum was adopted from Vegetation Carbon Project (VCP) under National Carbon Project (NCP). With the help of field data consisting mainly the height and girth information, volume of each individual tree per plot was obtained using site and tree species-specific standard volumetric equations. The phytomass was calculated by multiplying volume with Biomass Expansion Factor (BEF) then with regional specific gravity of the individual species and summed up in each plot to get total phytomass per plot. The total phytomass per plot was reported to be maximum 544.00 t/ha for linear TROF followed by 121.89 t/ha for block TROF. The carbon from phytomass was obtained by multiplying the total phytomass by a conversion factor that represents the average carbon content in phytomass. Spectral modeling for phytomass with different bands and indices were established and the best fit curve (R2 = 0.552) with red band was applied to generate phytomass and carbon distribution map of the study area.Banko Janakari, Vol. 24, No. 1, pp. 34-40


2021 ◽  
Vol 30 (4) ◽  
pp. 493-506
Author(s):  
S Kimm ◽  
SL Rauterberg ◽  
J Bill ◽  
J Stracke ◽  
N Kemper ◽  
...  

In this case study, a housing system for rabbits (Oryctolagus cuniculus) was developed, complying with the new German Welfare Regulation, and evaluated on-farm with regard to the rabbits' behaviour during four fattening periods. The housing system was characterised by the large group size of fatteners (maximum 65 animals per group, 12 animals per m²) due to the merging of six former single units for does and their litters, post-weaning. A large elevated platform, a box with a roof (small elevated platform), a tube and gnawing materials were made available per unit. The aim being to assess the suitability of the housing system for rabbits with regard to animal welfare, based on behavioural analyses. Therefore, the use of space by the rabbits (n = 247) was investigated by video analysis (instantaneous scan sampling) during daytime. Additionally, the individual behaviour of 20 focal rabbits in different locations was assessed by continuous sampling. Results showed that rabbits preferred to huddle together in the outer units in the first weeks post-weaning. The highest animal densities were found under and in front of the large and on the small platforms. The large platforms were visited increasingly from the 10th fattening day onwards. Elevated platforms supported resting and comfort behaviours. Nonelevated open-top areas enabled upright positions and locomotor behaviours. Aggression and stereotypic behaviours rarely occurred. We conclude that the housing system supported species-specific behaviour and seemed to cater for the needs of rabbits in terms of welfare. Nevertheless, further investigation is needed to ascertain the effects on animal health and performance.


2021 ◽  
pp. 1-13
Author(s):  
Heitor Felippe Uller ◽  
Laio Zimermann Oliveira ◽  
Aline Renata Klitzke ◽  
Joberto Veloso de Freitas ◽  
Alexander Christian Vibrans

Allometric models embedding independent variables such as diameter at breast height (d) and total height (h) are useful tools to predict the biomass of individual trees. Models for tropical forests are often constructed based on datasets composed of species with different morphological features and architectural models. It is reasonable to expect, however, that species-specific models may reduce uncertainties in biomass predictions, especially for palms, tree ferns, and trees with peculiar morphological features, such as stilt roots and hollow trunks. In this sense, three species with wide geographical distribution in the Brazilian Atlantic Forest were sampled, namely Euterpe edulis Mart., Cyathea delgadii Sternb., and Cecropia glaziovii Snethl., with the aim to (i) quantify their aboveground biomass (AGB), (ii) evaluate the AGB distribution in different plant compartments, (iii) fit species-specific models for predicting AGB at the individual level, and (iv) assess the performance of specific and generic models available in the literature to predict the AGB of individuals of these species. The compartment stem represented, on average, ∼74% of the total AGB of E. edulis individuals; in turn, the caudex compartment of C. delgadii represented, on average, ∼87% of the total AGB, while the trunk compartment of C. glaziovii represented, on average, ∼74%. Among the fitted models, the power model [Formula: see text] showed the best performance for E. edulis and C. delgadii. In turn, the asymptotic logistic model [Formula: see text], where dc is the diameter above the upper stilt root, presented the best performance for C. glaziovii. The variable h appeared as the most important predictor of AGB of E. edulis and C. delgadii; in contrast, the stem and caudex mean basic specific gravities were not suitable predictors. The fitted species-specific models outperformed the specific and generic models selected from the literature. They may, therefore, contribute to the reduction of uncertainties in AGB estimates. In addition, the results support evidence that specific models may be necessary for species with different growth forms and (or) peculiar morphological features, especially those with great abundance and wide geographic distribution.


1994 ◽  
Vol 195 (1) ◽  
pp. 35-51
Author(s):  
F M Kuenzi ◽  
T J Carew

Searching is an important component of several types of goal-directed behaviour. In soft-bodied animals, searching behaviour can appear quite complex because the range of body movement is not constrained by joints, limbs or muscles with discrete areas of origin and insertion. In addition, animals exhibiting this type of behaviour utilize their maximum freedom of movement. In this paper, we describe the head-waving searching behaviour of the sea hare Aplysia californica by characterizing patterns of movements and the changes in body shape that underlie these movements. A bout of head waving consists of a series of discrete movements separated by pauses. Each discrete movement lasts 4-10s and is directed either horizontally or vertically with respect to stationary part of the animal. Large movements, such as bending from the extreme right to the extreme left, consist of a series of these shorter movements separated by pauses lasting 1-2s. In all head-waving movements, the transverse axis of the head is kept relatively parallel with the substratum. Thus, vertical movements require only bending of the body, whereas horizontal movements require twisting of the body, particularly when the posture is more erect. During head waving, the anterior two-thirds of the body is free to move, but most of the bending occurs immediately posterior to the head region. There is no periodicity of movements within a bout of head waving, although isolated instances of repeated movements are sometimes observed. Therefore, although the individual movements during head waving are relatively simple, the absence of a patterned sequence accounts for the complexity of the overall behaviour. These observations both constrain models of the neural organization of head waving and provide criteria for categorizing head-waving movements in further behavioural and physiological studies.


eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Richard A Neher ◽  
Colin A Russell ◽  
Boris I Shraiman

Given a sample of genome sequences from an asexual population, can one predict its evolutionary future? Here we demonstrate that the branching patterns of reconstructed genealogical trees contains information about the relative fitness of the sampled sequences and that this information can be used to predict successful strains. Our approach is based on the assumption that evolution proceeds by accumulation of small effect mutations, does not require species specific input and can be applied to any asexual population under persistent selection pressure. We demonstrate its performance using historical data on seasonal influenza A/H3N2 virus. We predict the progenitor lineage of the upcoming influenza season with near optimal performance in 30% of cases and make informative predictions in 16 out of 19 years. Beyond providing a tool for prediction, our ability to make informative predictions implies persistent fitness variation among circulating influenza A/H3N2 viruses.


2001 ◽  
Vol 49 (4) ◽  
pp. 397 ◽  
Author(s):  
Ross L. Goldingay ◽  
Darren G. Quin ◽  
Sue Churchill

A detailed study was conducted over a 12-month period of 10 yellow-bellied glider groups at Nitchaga Creek in north Queensland. Adult gliders were sexually dimorphic in body size and were characterised by yellow ventral fur, which is consistent with southern populations. Gliders lived in groups of 3–6 individuals that occupied exclusive areas of about 50 ha. The structure of glider groups varied enormously: five contained one adult pair, three contained one adult male and 2–3 adult females, and two initially contained 2–3 adult males and one adult female but then persisted as bachelor groups after the death or disappearance of the adult female. Group size changed during the year as offspring matured and as individuals died. One male glider dispersed about 1 km from its natal home-range and became the dominant male in a nearby group. Young were born throughout the year, with a peak in the number of pouch-young in June. This study has confirmed the highly variable social system of the yellow-bellied glider, which appears to be mediated by local resource abundance.


1989 ◽  
Vol 3 (7) ◽  
pp. 877 ◽  
Author(s):  
S Bhatti ◽  
PJ Gullan

Three new genera and 11 new species from New Guinea are described in the tribe Monophlebulini. Erropera, gen, nov., contains four new species: E. ablusa, E. papuensis, E, pilosa and E. sedlaceki; Modicicoccus, gen. nov., contains four new species: M. gagnei, M. kaindiensis, M. monticolus and M. rtewsteadi; and Peengea, gen. nov., contains one new species: P. affinis. Two new species of Mottophlehirlus Cockerell, M. enarotalicus and M. gressitti, are described. The adult females of all 11 new species and the first instar nymphs of E. sedlaceki and P. affinis are described. A marsupium associated with the genital opening of the adult female is reported for the first time in the tribe Monophlebulini.


1984 ◽  
Vol 11 (1) ◽  
pp. 21 ◽  
Author(s):  
JC Merchant ◽  
K Newgrain ◽  
B Green

The growth and development, from 10 to 270 days old, of eastern quolls in a captive colony was recorded. Young were able to detach from the teat by 65 days of age and their eyes were open by 80 days. Statistically significant differences in some measurements from males and females were found as early as 85 days of age. The weaning period commenced at 102 days ofage, and coincided with eruption ofthe first molar teeth. Total independence, determined by the cessation of lactation in the mother, was as early as 142 days in litters of one or as late as 200 days in larger litters. There was a high correlation between litter size and age at independence. Lactation was maintained in all previously suckled mammary glands of adult females after the death of young aged 65 days or over if some siblings remained. This was due to the ability of young of this age to detach and reattach to the teats at will. The implication of this observation is that the commonly held view that the numbers of surviving young in marsupial litters corresponds to the number of lactating teats in the adult female may not always be correct.


2014 ◽  
Vol 104 (5) ◽  
pp. 652-660 ◽  
Author(s):  
B. Kumar ◽  
G. Mishra ◽  
Omkar

AbstractIn the present study predation parameters, i.e. consumption rate, conversion efficiency and growth rate, and total developmental duration of immature stages of two congeneric ladybirds, Coccinella septempunctata (L.) and Coccinella transversalis F., have been evaluated in presence of conspecific and heterospecific fourth instar larval and adult female tracks. We hypothesized that the semiochemicals within larval/adult female tracks might act as foraging/feeding deterrent pheromones (FDPs) and would reduce the predation parameters; and would prolong total developmental duration of ladybird predators. Results of the study positively affirmed our hypothesis. The deterrence in prey consumption and reduction in conversion efficiency and growth rate was density dependent with species-specific variations. Consumption rate, conversion efficiency, and growth rate of larval instars decreased and the total developmental duration of immature stages increased when exposed to an increasing density of zero, two, three, and four conspecific/heterospecific larval/adult female tracks. Between ladybird species, C. septempunctata had higher consumption rate, growth rate, and total developmental durations, whereas conversion efficiency was higher in C. transversalis. Despite the presence of semiochemical tracks as foraging barriers, early instars showed higher conversion efficiencies and growth rates, whereas fourth instars had highest consumption rate in all experimental treatments. The present study, therefore, suggests that semiochemical tracks significantly reduce the predation potential and prolong developmental duration of conspecifics and heterospecifics. They, thus behave as FDP.


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