Study Finds Female California Condors Can Reproduce without a Male
2021-11-02
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1A new study suggests that female California condor birds can reproduce without a male.
2Researchers with the San Diego Zoo Wildlife Alliance said genetic tests confirmed the findings.
3The group said that two baby males, called chicks, that hatched in 2001 and 2009 from unfertilized eggs, were related to their mothers.
4But neither chick was related to a male.
5The study was published last week in the Journal of Heredity.
6It is the first report of asexual reproduction in California condors.
7Reproduction from an unfertilized egg can happen in other animals such as sharks and bees.
8But in birds, it usually only takes place when females are not around males.
9In this case, each mother condor had bred with males before.
10The two mothers involved in the research had produced 34 chicks.
11Each was with a fertile male condor at the zoo when they produced the eggs without male help.
12The researchers said they believe it is the first case of asexual reproduction in any bird species where the female had access to a mate.
13Olivia Ryder leads genetics work for the San Diego Zoo Wildlife Alliance.
14She is also the study's co-writer.
15She said the findings raise questions about whether this kind of reproduction is happening in other species.
16The non-profit Wildlife Alliance runs the San Diego Zoo and Safari Park.
17It has been involved in a California condor reproduction program that helped save the huge birds from disappearing.
18California condors are the largest flying birds in North America.
19They used to be found throughout the West Coast.
20But only 22 remained in the 1980s when the U.S. government captured condors and placed them in zoos to increase their numbers.
21About 160 were raised at the San Diego Zoo and Safari Park.
22There are now more than 500 California condors, including more than 300 that have been released into the wild in California, Arizona, Utah and Mexico.
23The asexual reproduction was discovered a number of years ago.
24Testing of genetic material collected from condors, both living and dead, in reproduction programs and in the wild appeared to confirm the results.
25The study tested 467 male California condors to find out if they were related to the two birds in question.
26None of them were found to have a genetic connection.
27California condors can live up to 60 years.
28But the two male birds that hatched in 2001 and 2009 were not healthy.
29One was less than 2 years old when he died.
30The other lived less than eight years.
31I'm Ashley Thompson.
1A new study suggests that female California condor birds can reproduce without a male. 2Researchers with the San Diego Zoo Wildlife Alliance said genetic tests confirmed the findings. The group said that two baby males, called chicks, that hatched in 2001 and 2009 from unfertilized eggs, were related to their mothers. But neither chick was related to a male. 3The study was published last week in the Journal of Heredity. It is the first report of asexual reproduction in California condors. 4Reproduction from an unfertilized egg can happen in other animals such as sharks and bees. 5But in birds, it usually only takes place when females are not around males. In this case, each mother condor had bred with males before. The two mothers involved in the research had produced 34 chicks. Each was with a fertile male condor at the zoo when they produced the eggs without male help. 6The researchers said they believe it is the first case of asexual reproduction in any bird species where the female had access to a mate. 7Olivia Ryder leads genetics work for the San Diego Zoo Wildlife Alliance. She is also the study's co-writer. She said the findings raise questions about whether this kind of reproduction is happening in other species. 8The non-profit Wildlife Alliance runs the San Diego Zoo and Safari Park. It has been involved in a California condor reproduction program that helped save the huge birds from disappearing. 9California condors are the largest flying birds in North America. They used to be found throughout the West Coast. But only 22 remained in the 1980s when the U.S. government captured condors and placed them in zoos to increase their numbers. About 160 were raised at the San Diego Zoo and Safari Park. 10There are now more than 500 California condors, including more than 300 that have been released into the wild in California, Arizona, Utah and Mexico. 11The asexual reproduction was discovered a number of years ago. Testing of genetic material collected from condors, both living and dead, in reproduction programs and in the wild appeared to confirm the results. 12The study tested 467 male California condors to find out if they were related to the two birds in question. None of them were found to have a genetic connection. 13California condors can live up to 60 years. But the two male birds that hatched in 2001 and 2009 were not healthy. One was less than 2 years old when he died. The other lived less than eight years. 14I'm Ashley Thompson. 15The Associated Press reported this story Ashley Thompson adapted it for VOA Learning English. Mario Ritter, Jr. was the editor. 16______________________________________________________________ 17Words in This Story 18hatch -v. to be born by coming out of an egg 19asexual -adj. (scientific) of or relating to a kind of reproduction that does not involve the combining of male and female cells 20access -n. the ability to get something, enter a place or meet someone 21We want to hear from you. Write to us in the Comments section, and visit our Facebook page.