Search results
Results From The WOW.Com Content Network
Birds feature in the flag designs of 17 countries and numerous subnational entities and territories. [326] Birds are used by nations to symbolise a country's identity and heritage, with 91 countries officially recognising a national bird. Birds of prey are highly represented, though some nations have chosen other species of birds with parrots ...
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. Commonly occurring sexual dimorphisms such as size and color differences are energetically costly attributes that signal competitive breeding ...
The sequence and variety of courting behaviors vary widely among species, but they typically begin with territorial defense, followed by mate-attraction displays, and selection of a nest site. [4] Seabirds are long-lived, socially monogamous, birds that usually mate for life. This makes selecting a mate extremely important with lifelong ...
Female birds are able to produce more of a certain gender of birds that are more likely to survive under extreme conditions. In birds, the females' egg determines the gender of the offspring, not the male's sperm. In zebra finches, a study showed the effect of food on gender ratio production. For females, egg production is a metabolically ...
A boa constrictor in the U.K. gave birth to 14 babies — without a mate. The process is called parthenogenesis, from the Greek words for “virgin” and “birth.” It tends to occur in ...
How do birds get their colors? Understanding bird coloration combines biology and physics. There are two primary ways that birds get their color: pigmentation and the physical structure of the ...
In some birds, it includes behaviors such as nest-building and feeding offspring. The human practice of mating and artificially inseminating domesticated animals is part of animal husbandry . In some terrestrial arthropods , including insects representing basal (primitive) phylogenetic clades, the male deposits spermatozoa on the substrate ...
A multi-purpose opening terminating at the vent at the posterior of a bird: birds expel waste from it; most birds mate by joining cloaca (a "cloacal kiss "); and females lay eggs from it. Birds do not have a urinary bladder or external urethral opening and (with exception of the ostrich ) uric acid is excreted from the cloaca, along with faeces ...