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12. Life cycles in polar arthropods - flexible or programmed?
- Creator:
- Danks, Hugh V.
- Format:
- print, text, and regular print
- Type:
- article, bibliography, conference publication, model:article, and TEXT
- Subject:
- Arctic, Third European Workshop of Invertebrate Ecophysiology (1998 : Birmingham, Česko), climate, temperature, seasonal, life-cycle, arthropods, insects, polar, Antarctic, zoologie, fyziologie živočichů, ekofyziologie, členovci, hmyz, životní cykly, sezónní vlivy, klimatické vlivy, teplota, arktická oblast, antarktická oblast, fenologická studie, přehledy, 591.5, 061.3, and 595.2/.7
- Language:
- English
- Description:
- Climate features that influence life cycles, notably severity, seasonality, unpredictability and variability, are summarized for different polar zones. The zones differ widely in these factors and how they are combined. For example, seasonality is markedly reduced by oceanic influences in the Subantarctic. Information about the life cycles of Arctic and Antarctic arthropods is reviewed to assess the relative contributions of flexibility and programming to life cycles in polar regions. A wide range of life cycles occurs in polar arthropods and, when whole life cycles are considered, fixed or programmed elements are well represented, in contrast to some recent opinions that emphasize the prevalence of flexible or opportunistic responses. Programmed responses ale especially common for controlling the appearance of stages that are sensitive to adverse conditions, such as the reproductive adult. The relative contribution of flexibility and programming to different life cycles is correlated with taxonomic affinity (which establishes the general lifecycle framework for a species), and with climatic zone, the habitats of immature and adult stages, and food., Hugh V. Danks, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
13. Obituary: Professor Ladislav Janský, D.Sc
- Creator:
- Růžena Novotná
- Format:
- print, bez média, and svazek
- Type:
- article, nekrology, model:article, and TEXT
- Subject:
- Biografie, Janský, Ladislav, 1931-2007, vědecká práce, osobnosti, ekofyziologie, scientific work, ecophysiology, celebrities, 8, and 929
- Language:
- English
- Description:
- R. Novotná.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14. Periods of dormancy and cohort-splitting in the millipede Polydesmus angustus (Diplopoda: Polydesmidae)
- Creator:
- David, Jean-François, Celerier, Marie-Louise, and Geoffroy, Jean-Jacques
- Format:
- print, text, and regular print
- Type:
- article, bibliography, conference publication, model:article, and TEXT
- Subject:
- Third European Workshop of Invertebrate Ecophysiology (1998 : Birmingham, Česko), zoologie, fyziologie živočichů, ekofyziologie, hmyz, Diplopoda, Polydesmus angustus, životní cyklus, reprodukční dormance, diapauza, sezónní vlivy, 591.5, 061.3, and 595.2/.7
- Language:
- English
- Description:
- First stadium juveniles of P. angustus were reared under controlled seasonal conditions to maturity, reproduction and death. Individuals born in any one breeding season either had a 1-year or a 2-year life cycle (cohort-splitting). The life cycle was annual for individuals born in the first part of the breeding season (May-August), but became biennial for those born later (August-October). Two phenomena were involved: (1) Only individuals reaching the penultimate stadium (stadium VII) before a critical period at the end of spring could become adult in the breeding season following that of their birth. After this time, stadium VII individuals entered into aestivation and only became adult in the second autumn after their birth. (2) Females becoming adult in autumn entered reproductive dormancy and only laid eggs in the following spring. Overall, individuals born at the start of the breeding season easily reached stadium VII before the critical period and were able to breed at I year, whereas individuals born at the end of the breeding season reached stadium VII after the critical period, then had two consecutive periods of dormancy and only bred at 2 years age. Individuals from the same nest born in the middle of the breeding season (August) could have either annual or biennial life cycles, depending on whether they reached stadium VII before or during aestivation. The environmental factors capable of triggering aestivation in subadults and reproductive dormancy in autumn-maturing females are discussed., Jean-Francois David, Marie-Louise Celerier, Jean-Jacques Geoffroy, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
15. Site latitude influences on respiration rate, fat content and the ability of worker ants to rear larvae: A comparison of Myrmica rubra (Hymenoptera: Formicidae) populations over their European range
- Creator:
- Elmes, Graham W., Radchenko, Alexander G., Barr, Boyd, Wardlaw, Judith C., Nielsen, Mogens G., Kipyatkov, Vladilen E., and Lopatina, Elena B.
- Format:
- print, text, and regular print
- Type:
- article, bibliography, conference publication, model:article, and TEXT
- Subject:
- zoologie, fyziologie živočichů, ekofyziologie, hmyz, mravenci, Myrmica rubra, dýchání, obsah tuku, péče o larvy, hranice rozšíření, vliv zeměpisné polohy, 591.5, 061.3, and 595.2/.7
- Language:
- English
- Description:
- Myrmica rubra is a northern, temperate Palaearctic ant species with a geographical range that extends from the Atlantic coast of Europe to central Asia. In Europe, its range covers > 25° of latitude where it lives under a variety of climates that vary from extreme oceanic in the west, to continental in the east. Colonies nest in the soil and their life cycles are known to be highly dependent on ambient temperature and soil moisture. We hypothesised that the brood-rearing behaviour of populations might be focally adapted to climate and that we might detect differences when the ants were reared under \"common-garden\" conditions. Brood-rearing behaviour was compared for 38 colonies of M. rubra drawn from 13 populations representing a range of 6 latitudes: all 6 were represented in eastern Europe and 2 in western Europe. A sample of ants from each colony was used to estimate respiration rate, body mass and fat content at the start of the experiment in spring (immediately post hibernation) and at the end of the experiment (mid summer). Respiration had a linear relationship with latitude, with northern populations having greater respiration rate in spring compared to southern populations. It is suggested that this is an adaptation to different seasonality over the species' range that results in the \"more active\" northern workers rearing fewer brood to maturity more quickly than southern workers. Fat content, a measure of worker \"quality\", had a parabolic relationship with latitude with mid latitude colonies having the fattest workers. Fatter workers appeared to rear heavier brood. This probably represented a functional response to environment with populations living at \"edge of range\" sites being physiologically more stressed and performing brood-rearing tasks less well than centre of range populations. We believe that this is the first demonstration of a consistent, intra-specific trend for Variation in the social physiology of an ant species over its geographic range., Graham W. Elmes, Judith C. Wardlaw, Mogens G. Nielsen, Vladilen E. Kipyatko, Elena B. Lopatina, Alexander G. Radchenko, Boyd Barr, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
16. Species at the edge of their range: The significance of the thermal environment for the distribution of congeneric Craspedolepta species (Sternorrhyncha: Psylloidea) living on Chamerion angustifolium (Onagraceae)
- Creator:
- Bird, Jeremy M. and Hodkinson, Ian D.
- Format:
- print, text, and regular print
- Type:
- article, bibliography, conference publication, model:article, and TEXT
- Subject:
- Third European Workshop of Invertebrate Ecophysiology (1998 : Birmingham, Česko), zoologie, fyziologie živočichů, ekofyziologie, hmyz, Psylloidea, Craspedolepta nebulosa, Craspedolepta subpunctata, výskyt, rozšíření, životní cyklus, fenologie, ekologické faktory, teplota, sezónní vlivy, 591.5, 061.3, and 595.2/.7
- Language:
- English
- Description:
- There is much current discussion about the factors that control the distribution and abundance of animal species, particularly at the edges of their range. The significance of temperature for survival and development is compared in two closely related psyllid species (Craspedolepta nebulosa and C. subpunctata) living on the same host plant (Chamerion angustifolium) (Onagraceae) but displaying different distributions along latitudinal and altitudinal gradients. The following measurements were made at critical periods during the life cycle (a) winter supercooling points (SCPs), (b) tolerance of short (1 min) and long term (1-25) days exposure to sub-zero temperatures above the SCP, (c) tolerance of short term exposure to high spring/summer temperatures and (d) comparative field development rates among species and sites during the early critical part of the growing season. Successful completion of the life cycle is related to heat availability during the growing season. This appears to limit the distribution of the Craspedolepta species, rather than their survival response to thermal extremes. No significant differences were found between the two species in the supercooling point or in their long and short term survival responses at low or high temperatures., Jeremy M. Bird, Ian D. Hodkinson, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
17. Temperature, development and establishment potential of Thrips palmi (Thysanoptera: Thripidae) in the United Kingdom
- Creator:
- McDonald, Jamie R., Bale, Jeffrey S., and Walters, Keith F.A.
- Format:
- print, text, and regular print
- Type:
- article, bibliography, conference publication, model:article, and TEXT
- Subject:
- Third European Workshop of Invertebrate Ecophysiology (1998 : Birmingham, Česko), zoologie, fyziologie živočichů, ekofyziologie, hmyz, Thysanoptera, Thripidae, Thrips palmi, Frankliniella occidentalis, vývoj, přezimování, teplota, teplotní biologie, 591.5, 061.3, and 595.2/.7
- Language:
- English
- Description:
- In order to manage the risks posed to domestic crop production by quarantine pests such as Thrips palmi, their potential to establish in a new environment must be assessed. The thermal requirements for development of T. palmi were determined and compared with UK temperatures, to estimate its potential for development under UK conditions. Temperature and rate of development of T. palmi from egg to adult were linearly related between 15 and 30°C, allowing calculation of an overall threshold of 10.1°C, and a sum of effective temperatures of 194 degree-days. In the UK, development of T. palmi would be possible outdoors during the summer when a maximum of up to four or five generations could occur. Comparison of these data with those of the recently established and biologically similar pest, Frankliniella occidentalis, shows that establishment of T. palmi in the UK is unlikely to be limited by an inability to complete the life cycle during the favourable season., Jamie R. McDonald, Jeffrey S. Bale, Keith F.A. Walters, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
18. The influence of thermal acclimation on the amylolytic activity and microanatomy of the alimentary tract of the oribatid mite Galumna elimata (Acari: Oribatei)
- Creator:
- Šustr, Vladimír and Jan Hubert
- Format:
- print, text, and regular print
- Type:
- article, bibliography, conference publication, model:article, and TEXT
- Subject:
- Third European Workshop of Invertebrate Ecophysiology (1998 : Birmingham, Česko), zoologie, fyziologie živočichů, ekofyziologie, roztoči, Oribatei, Galumna elimata, trávicí trakt, trávicí enzymy, amylolytická aktivita, teplota, teplotní aklimatizace, 591.5, 061.3, and 595.2/.7
- Language:
- English
- Description:
- The oribatid mite Galumna elimata was reared under laboratory conditions on algae (Protacoccus spp.) at different temperatures (5, 15 and 20°C). Higher weight-specific amylolytic activity was found in the whole body homogenates of mites exposed to cold acclimation (5°C, 21 days) in comparison with individuals acclimated to 15 and 20°C. Accompanying parameters (live body weight, content of total soluble proteins in the body, protein-specific amylolytic activity, presence and composition of food boluses, activity of mesenteric and caecal wall cells, gregarinid parasitisation, number of glycogen granulae and guanine deposits in mesenchymal tissue, presence of proventricular glands) were investigated at all three acclimation temperatures to explain mechanisms of this change. The acclimation response of weight-specific amylolytic activity was accompanied by elevation of protein-specific amy lolytic activity. Microanatomical features did not confirm any increased secretion activity of mesenteric and caecal cells in cold acclimated animals. Granulation and apocrine secretion of these cells increased with increasing temperature as with food ingestion. The food boluses contained algae or algae mixed with unknown fungal hyphae in individuals acclimated to 15 and 20°C. The concentrated mucoid substances prevailed in animals exposed to cold, indicating lower feeding activity at 5°C. Based on these findigs, Lye hypothesised that specific amylolytic activity reflected passively the different changes in protein composition of the body at different temperatures and its elevation is without direct adaptive importance., Vladimír Šustr, Jan Hubert, and Lit
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public