نتایج جستجو برای: valley of butterflies

تعداد نتایج: 21168178  

Journal: :Integrative and comparative biology 2008
Robert B Srygley Robert Dudley

Directed aerial displacement requires that a volant organism's airspeed exceeds ambient wind speed. For biologically relevant altitudes, wind speed increases exponentially with increased height above the ground. Thus, dispersal of most insects is influenced by atmospheric conditions. However, insects that fly close to the Earth's surface displace within the flight boundary layer where insect ai...

Journal: :Conservation biology : the journal of the Society for Conservation Biology 2009
Sandra B Muriel Gustavo H Kattan

Determining the permeability of different types of landscape matrices to animal movement is essential for conserving populations in fragmented landscapes. We evaluated the effects of habitat patch size and matrix type on diversity, isolation, and dispersal of ithomiine butterflies in forest fragments surrounded by coffee agroecosystems in the Colombian Andes. Because ithomiines prefer a shaded ...

Journal: :تحقیقات جغرافیایی 0
غلام حسن جعفری دانشگاه زنجان اضغر رستم خانی دانشگاه زنجان

condition of contour lines in topographic maps, explains more geomorphologic issues such as effective processes in the land forms found in nature. change in the curvature of the transverse profile of a valley in mountainous areas, the peak of the mountain range, also reflect the geomorphologic features and expresses the tectonic events and climate changes occurring in the region. these changes ...

Journal: :تحقیقات جغرافیایی 0
مریم عزتی دانشکده علوم دانشگاه گلستان، مریم آق آتابای دانشکده ی علوم دانشگاه گلستان مریم آق آتابای دانشکده ی علوم دانشگاه گلستان

study area is located in the central kopehdagh north of bojnurd and shirvan cities, between kakli and raz villages. aim of this research is separating high activity area from low activity. in this study, in order to evaluate rate of tectonic activity, stream length-gradient index (sl), ratio of valley floor width to valley height (vf), transverse topographic system (t), hypsometric integral (hi...

Journal: :Proceedings. Biological sciences 2004
Anne Lyytinen Paul M Brakefield Leena Lindström Johanna Mappes

The butterfly Bicyclus anynana exhibits phenotypic plasticity involving the wet-season phenotype, which possesses marginal eyespots on the ventral surface of the wings, and the dry-season form, which lacks these eyespots. We examined the adaptive value of phenotypic plasticity of B. anynana in relation to the defence mechanisms of crypsis and deflection. We assessed the visibility differences b...

Journal: :Philosophical transactions of the Royal Society of London. Series B, Biological sciences 2011
Michiyo Kinoshita Kei Yamazato Kentaro Arikawa

The human eye is insensitive to the angular direction of the light e-vector, but several animal species have the ability to discriminate differently polarized lights. How the polarization is detected is often unclear, however. Egg-laying Papilio butterflies have been shown to see false colours when presented with differently polarized lights. Here we asked whether this also holds in foraging bu...

2011
Mikael A. Carlsson Sonja Bisch-Knaden Alexander Schäpers Raimondas Mozuraitis Bill S. Hansson Niklas Janz

Butterflies are believed to use mainly visual cues when searching for food and oviposition sites despite that their olfactory system is morphologically similar to their nocturnal relatives, the moths. The olfactory ability in butterflies has, however, not been thoroughly investigated. Therefore, we performed the first study of odour representation in the primary olfactory centre, the antennal l...

Rhamnus pallasii is one of important and valuable species in Khalkhal forest area.This study aimed to determine the relationship between vegetation properties of Rhamnus pallasii with soil and physiographic factors in this forest reserve. For this purpose, from 1030 to 2540 m.a.s.l, 48 sample plots of circular shape with an area of 500 m2, in three land forms (ridge, valley and slope) in four a...

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