Leal Manuel
Department of Biology, Union College, Schenectady, New York, 12308, USA.
Am Nat. 2004 Jan;163(1):26-39. doi: 10.1086/379794. Epub 2003 Dec 24.
We tested the prediction of the sensory drive hypothesis using four allopatric populations of the lizard Anolis cristatellus from two distinct environments (i.e., mesic and xeric conditions). For each population, we measured habitat light characteristics and quantified signal design by measuring the spectral and total reflectance and transmittance of the dewlap. We used these data to calculate dewlap detectability using an empirically based model of signal detection probability. We found that populations from mesic and xeric conditions occupy two distinct habitats with respect to light intensity and spectral quality and that dewlap design has diverged between populations in a way that increases signal detectability in each habitat. The major difference in dewlap design was in total reflectance and transmittance, making dewlaps from xeric habitats darker and dewlaps from mesic habitats brighter. Furthermore, dewlap detection decreased significantly when a dewlap from a xeric habitat is detected under the spectral conditions of a mesic habitat. The converse is true for a dewlap from a mesic habitat. We propose that sensory drive has promoted divergence in dewlap design in distinct habitat light conditions, and we discuss the possibility that selection might promote early stages of reproductive isolation as a by-product of selection on dewlap design to distinct habitat light conditions.
我们利用来自两种不同环境（即湿润和干旱条件）的四个安乐蜥（Anolis cristatellus）异域种群，对感官驱动假说的预测进行了测试。对于每个种群，我们测量了栖息地的光照特征，并通过测量喉扇的光谱反射率、总反射率和透射率来量化信号设计。我们使用这些数据，通过基于经验的信号检测概率模型来计算喉扇的可检测性。我们发现，来自湿润和干旱条件的种群在光照强度和光谱质量方面占据了两个不同的栖息地，并且喉扇设计在种群之间已经发生了分化，这种分化方式提高了每个栖息地中信号的可检测性。喉扇设计的主要差异在于总反射率和透射率，使得来自干旱栖息地的喉扇颜色更深，而来自湿润栖息地的喉扇颜色更亮。此外，当在湿润栖息地的光谱条件下检测来自干旱栖息地的喉扇时，喉扇的可检测性显著降低。对于来自湿润栖息地的喉扇，情况则相反。我们提出，感官驱动促进了在不同栖息地光照条件下喉扇设计的分化，并且我们讨论了选择可能作为对不同栖息地光照条件下喉扇设计选择的副产品，促进生殖隔离早期阶段的可能性。
