Physiological correlates of ecological divergence along an urbanization gradient: differential tolerance to ammonia among molecular forms of the malaria mosquito Anopheles gambiae.
Physiological correlates of ecological divergence along an urbanization gradient: differential tolerance to ammonia among molecular forms of the malaria mosquito Anopheles gambiae.
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DOI：
10.1186/1472-6785-13-1
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发表时间：
2013-01-07
期刊：
影响因子：
--
通讯作者：
Costantini C
中科院分区：
文献类型：
--
作者：
Tene Fossog B;Antonio-Nkondjio C;Kengne P;Njiokou F;Besansky NJ;Costantini C
生物耐受环境压力的能力的限制影响了它们的基本生态位，并限制了它们在特定栖息地的分布。因此，耐受性的进化可以产生生态位动态。非洲热带疟蚊冈比亚按蚊（Anopheles gambiae）的森林种群已被证明能够适应历史上不适宜的幼虫栖息地，这些栖息地被喀麦隆人口稠密的城市群中发现的腐烂的有机物污染。这一过程导致了生态位从农村向城市环境的扩展，这与该分类单元中两个进化上重要的单位M和S的隐物种形成和生态分化有关，其中生殖隔离是重要的，但仍不完全。两种形态之间的栖息地隔离导致了临床上的不规则斑块的马赛克分布，M型主要分布在城市群中心，S型主要分布在周围的农村地区。我们推测，对有机物分解产生的含氮污染物（其中氨是对水生生物毒性最大的污染物）的耐受性的发展可能会影响M形式的分布模式和生态位扩展过程。急性毒性生物测定表明，在喀麦隆首都雅温得的极端城市化梯度中出现的两种分子形式的种群对氨的反应不同。最能描述剂量-死亡率曲线的回归线在解释变量的尺度（S型氨浓度为对数变换，M型氨浓度为线性）和斜率（S型氨浓度较陡，M型氨浓度较浅）上存在差异。通过概率分析，这些特征反映了两个种群中个体耐受阈值频率分布的差异，与S型相比，M型表现出更大的均值和方差。与基于雅温得幼虫栖息地的生境划分和氨暴露模式的预期一致，M型比S型对氨的耐受性更强。这种特性可能是生理机制的一部分，允许M型森林种群在受污染的幼虫栖息地定居，这是其在喀麦隆人口稠密的人类住区中生态位扩张的核心。
Limitations in the ability of organisms to tolerate environmental stressors affect their fundamental ecological niche and constrain their distribution to specific habitats. Evolution of tolerance, therefore, can engender ecological niche dynamics. Forest populations of the afro-tropical malaria mosquito Anopheles gambiae have been shown to adapt to historically unsuitable larval habitats polluted with decaying organic matter that are found in densely populated urban agglomerates of Cameroon. This process has resulted in niche expansion from rural to urban environments that is associated with cryptic speciation and ecological divergence of two evolutionarily significant units within this taxon, the molecular forms M and S, among which reproductive isolation is significant but still incomplete. Habitat segregation between the two forms results in a mosaic distribution of clinally parapatric patches, with the M form predominating in the centre of urban agglomerates and the S form in the surrounding rural localities. We hypothesized that development of tolerance to nitrogenous pollutants derived from the decomposition of organic matter, among which ammonia is the most toxic to aquatic organisms, may affect this pattern of distribution and process of niche expansion by the M form. Acute toxicity bioassays indicated that populations of the two molecular forms occurring at the extremes of an urbanization gradient in Yaounde, the capital of Cameroon, differed in their response to ammonia. The regression lines best describing the dose-mortality profile differed in the scale of the explanatory variable (ammonia concentration log-transformed for the S form and linear for the M form), and in slope (steeper for the S form and shallower for the M form). These features reflected differences in the frequency distribution of individual tolerance thresholds in the two populations as assessed by probit analysis, with the M form exhibiting a greater mean and variance compared to the S form. In agreement with expectations based on the pattern of habitat partitioning and exposure to ammonia in larval habitats in Yaounde, the M form showed greater tolerance to ammonia compared to the S form. This trait may be part of the physiological machinery allowing forest populations of the M form to colonize polluted larval habitats, which is at the heart of its niche expansion in densely populated human settlements in Cameroon.
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影响因子：
2.7
作者：
Djogbenou, Luc;Pasteur, Nicole;Chandre, Fabrice
通讯作者：
Chandre, Fabrice
影响因子：
3.8
作者：
della Torre, A;Tu, ZJ;Petrarca, V
通讯作者：
Petrarca, V
DOI：
10.1098/rspb.2008.1601
发表时间：
2009-04-22
影响因子：
4.7
作者：
Bridle, Jon R.;Gavaz, Sedef;Kennington, W. Jason
通讯作者：
Kennington, W. Jason
影响因子：
3
作者：
Caputo B;Nwakanma D;Jawara M;Adiamoh M;Dia I;Konate L;Petrarca V;Conway DJ;della Torre A
通讯作者：
della Torre A
影响因子：
2.2
作者：
Borash, DJ;Pierce, VA;Mueller, LD
通讯作者：
Mueller, LD