Many owners of birds particularly poultry and parrot species find it very difficult to determine the gender or sex of their avian pets and often need their veterinarian or their local bird-breeder to sex their birds for them. Appearance: Drab, mottled brown in the case of the female birds; brightly tufted heads, orange faces, black chests, and a large ruff of ornamental feathers in the case of most males. Parents have supposedly explained human reproduction to children in terms of the birds and the bees; if birds were really used to make this explanation, it would be widely believed that fertilization occurs after the briefest period of proximity of the waste elimination organs. BERKELEY, CA—With not a single scientist having successfully observed the behavior despite extensive ongoing research, the field of biology has made no progress in its understanding of how birds have sex, experts at the University of California told reporters Wednesday. All rights reserved.
As it is with people, birds also go through similar steps to ultimately produce offspring.
The highly unusual "semi-identical" Australian twins reported last week are the result of a rare event. Developing bird embryos do have penis precursors, it turns out, but a genetic signal causes the penis cells to die off during gestation. For more from Dr. Birds do it, bees do it -- but how? Sexual selection in birds concerns how birds have evolved a variety of mating behaviors, with the peacock tail being perhaps the most famous example of sexual selection and the Fisherian runaway.
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