排序方式: 共有3条查询结果,搜索用时 78 毫秒
1
1.
Jaime A. Teixeira da Silva Panagiotis Tsigaris 《Frontiers of Environmental Science & Engineering》2023,17(3):39
James E. Lovelock, famed for his Gaia hypothesis, which views the Earth as a living integrated and interconnected self-regulating system whose equilibrium comes about from complex energy-based interactions and feedback loops, ultimately sustaining life, passed away at the end of July, 2022 at the age of 103. Not only are the adaptive mechanisms of Gaia central to the conversation of environmental homeostasis, they lie at the heart of climate change and global warming. Lovelock is also remembered as the co-inventor of the electron capture detector that eventually allowed for the sensitive detection of chlorofluorocarbons and pesticides. Finally, Lovelock’s free-spirited nature and research independence allow academia to rethink current research’s modus operandi. 相似文献
2.
Kathryn E. Gardner Robin L. Foster Sean O’Donnell 《Behavioral ecology and sociobiology》2007,61(5):783-792
Bumblebee colonies experience daily and seasonal fluctuations in ambient temperature, but proper brood development requires
a stable nest temperature. This study examined how adaptive colony responses to changing ambient temperature are achieved
through the in-nest workers’ behavioral plasticity. We studied three Bombus huntii colonies in the laboratory. In the first experiment, we manipulated ambient temperature and recorded brood cell incubation
and wing fanning by individually marked, known-age bees. The colonies maintained their nests closer to appropriate brood development
temperatures (28 to 32°C) when exposed to a range of ambient temperatures from 10.3 to 38.6°C. Incubation activity was greater
in cooler treatment conditions, whereas in the highest temperature treatment, some bees fanned and others moved off the brood.
As the ambient temperature dropped, workers increased the duration of their incubating bouts, but, except at the highest temperature,
the number of workers that incubated did not differ significantly among treatments. A subset of the bees incubated significantly
more than their nest mates, some of which never incubated. Worker body size, but not age, was a good predictor of incubation
rates, and smaller bees incubated at higher rates. In the second experiment, we removed the most actively incubating workers.
Immediately after removals, the total colony incubation effort was lower than pre-removal levels, but incubation effort rebounded
toward pre-removal levels after 24 h. The increased thermoregulatory demand after removals was met primarily by bees increasing
their rates of incubation rather than by bees switching from a different task to incubation. We conclude that some B. huntii workers specialize on nest thermoregulation, and that changes in work rates are more important than task switching in meeting
thermal challenges. 相似文献
3.
Aging and demographic plasticity in response to experimental age structures in honeybees (<Emphasis Type="Italic">Apis mellifera</Emphasis> L) 总被引:1,自引:0,他引:1
Rueppell O Linford R Gardner P Coleman J Fine K 《Behavioral ecology and sociobiology》2008,62(10):1621-1631
Honeybee colonies are highly integrated functional units characterized by a pronounced division of labor. Division of labor
among workers is mainly age-based, with younger individuals focusing on in-hive tasks and older workers performing the more
hazardous foraging activities. Thus, experimental disruption of the age composition of the worker hive population is expected
to have profound consequences for colony function. Adaptive demography theory predicts that the natural hive age composition
represents a colony-level adaptation and thus results in optimal hive performance. Alternatively, the hive age composition
may be an epiphenomenon, resulting from individual life history optimization. We addressed these predictions by comparing
individual worker longevity and brood production in hives that were composed of a single-age cohort, two distinct age cohorts,
and hives that had a continuous, natural age distribution. Four experimental replicates showed that colonies with a natural
age composition did not consistently have a higher life expectancy and/or brood production than the single-cohort or double-cohort
hives. Instead, a complex interplay of age structure, environmental conditions, colony size, brood production, and individual
mortality emerged. A general tradeoff between worker life expectancy and colony productivity was apparent, and the transition
from in-hive tasks to foraging was the most significant predictor of worker lifespan irrespective of the colony age structure.
We conclude that the natural age structure of honeybee hives is not a colony-level adaptation. Furthermore, our results show
that honeybees exhibit pronounced demographic plasticity in addition to behavioral plasticity to react to demographic disturbances
of their societies. 相似文献
1