ML96728941
- 年龄
- 未说明
- 性别
- 未说明
媒体文件注释
A lodgepole pine cone. Cones in the South Hills and Albion Mountains have elevated defenses against crossbills because of selection exerted by crossbills. This includes thicker scales in the distal half of the cone where crossbills generally forage for seeds. These cones have also lost defenses against American red squirrels because these squirrels are absent. Squirrels prefer cones with more seeds and a higher ratio of seed mass to cone mass, and thus the cones in the South Hills have around three times as many seeds (and ~3 times as much seed mass to cone mass) in them than where red squirrels are present. This photograph was taken on 8 June 2014
观察细节
These photos represent two male Cassia Crossbills, the cones they forage on, and their habitat in the South Hills. Not all photographs were taken on the same day, and the date each was taken is noted.
技术信息
- 型号
- NIKON D610
- ISO
- 200
- 焦距
- 105 mm
- 闪光
- Flash did not fire, auto
- 光圈
- f/9.0
- 快门速度
- 0.02 sec
- 尺寸
- 4018 pixels x 2677 pixels
- 原始文件大小
- 2.47 MB