From: Tom & Jo Heindel
Date: 2/10/01
Time: 1:24:02 PM
Remote Name: 209.221.198.40
If a species exhibits a character that is typical of the other subspecies the result is a intergrade. If an intergrade mates with a pure bird cross-backs can occur where a bird goes from carrying half the genes of one race and half the genes of the other race to carrying 1/4 and 3/4. And if it happens again to 1/8 and 7/8. The later may explain the bird that Chris and Rosie had that has all the marks of one race (Red-shafted) and only one mark of the other race (Yellow-shafted). The intergrade we had in our yard a couple of weeks ago looked very similar to their bird except that the red crescent was single and only faintly red. All Northern Flickers and Nuttall's Woodpeckers should be carefully examined as we are the lucky ones having intergrades of both, albeit rarely, in the county.