| 单词 | parthenogenesis |
| 例句 | I remember: If your twin sister wasn’t my spitting image I’d swear you came about from parthenogenesis. I'll Give You the Sun 2014-09-16T00:00:00Z But to this viewer, at least, it’s a sincere tribute to the parthenogenesis of a pinup. Rock ’n’ Roll Swindles, Revisited 2022-05-30T04:00:00Z Only two of the eggs Saphira produced through parthenogenesis were able to develop enough to hatch. This lizard has no dad — here’s how 2019-06-28T04:00:00Z But those offspring were made by tinkering with egg cells in laboratory dishes rather than by giving female animals the capacity for virgin birth, also known as parthenogenesis. ‘Virgin Birth’ Engineered into Female Animals for First Time 2023-08-01T04:00:00Z An estimated 76 percent of fruit flies can exhibit parthenogenesis, but as to why some can and some can't was a mystery. Fly-ing solo: scientists discover genetic on-switch for "virgin birth" in fruit flies 2023-07-28T04:00:00Z "Certain temperature conditions may foster all-female populations, which can be overcome through facultative parthenogenesis," he said. Why a crocodile’s ‘virgin birth’ isn’t a miracle 2023-06-10T04:00:00Z Virgin births, known as parthenogenesis, happen when an unfertilised egg develops into an embryo. Crocodile’s ‘Virgin Birth’ Is a First for Science’s History Books 2023-06-09T04:00:00Z Because of this, the park's scientific team contacted a US team from Virginia Polytechnic, which specialised in virgin births, known scientifically as parthenogenesis. Crocodile found to have made herself pregnant 2023-06-07T04:00:00Z Earlier research identified candidate genes for parthenogenesis, says study co-author Alexis Sperling, a developmental biologist at the University of Cambridge, UK. ‘Virgin Birth’ Engineered into Female Animals for First Time 2023-08-01T04:00:00Z To try and find an answer, Sperling and her colleagues sequenced the genomes of two types of Drosophila mercatorum fruit flies, one that needed males to reproduce and another that reproduces by parthenogenesis. Fly-ing solo: scientists discover genetic on-switch for "virgin birth" in fruit flies 2023-07-28T04:00:00Z The discovery is a bit fortuitous as it coincides with the 30th anniversary of "Jurassic Park," which prominently features parthenogenesis in dinosaurs. Why a crocodile’s ‘virgin birth’ isn’t a miracle 2023-06-10T04:00:00Z Even when there are males around, females may still use parthenogenesis. Crocodile’s ‘Virgin Birth’ Is a First for Science’s History Books 2023-06-09T04:00:00Z It is unclear why parthenogenesis occurs in different species, but occurrences are cropping up in the scientific literature more often, probably because researchers are now looking for it. Crocodile found to have made herself pregnant 2023-06-07T04:00:00Z But many species of insect and lizard, as well as other animals, have also evolved parthenogenesis, which requires no genetic contribution from a male, as an alternative to sex. ‘Virgin Birth’ Engineered into Female Animals for First Time 2023-08-01T04:00:00Z Once they identified the genes, they started trying to essentially turn it on in the fruit flies that they knew couldn't reproduce by parthenogenesis. Fly-ing solo: scientists discover genetic on-switch for "virgin birth" in fruit flies 2023-07-28T04:00:00Z It's the first time scientists have recorded in an American crocodile successful parthenogenesis, which is asexual reproduction and Greek for "virgin birth." Why a crocodile’s ‘virgin birth’ isn’t a miracle 2023-06-10T04:00:00Z For example, many cases of parthenogenesis have been discovered in geckos, snakes and lizards that live in dry and harsh climates such as high altitudes. Crocodile’s ‘Virgin Birth’ Is a First for Science’s History Books 2023-06-09T04:00:00Z One theory is that it happens in species capable of parthenogenesis when numbers dwindle, and they are on the verge of extinction. Crocodile found to have made herself pregnant 2023-06-07T04:00:00Z The comparison allowed the authors to identify 44 genes that were potentially involved in parthenogenesis. ‘Virgin Birth’ Engineered into Female Animals for First Time 2023-08-01T04:00:00Z Despite the ways it's often portrayed in the media as a "virgin birth," parthenogenesis isn't a biblical miracle. Fly-ing solo: scientists discover genetic on-switch for "virgin birth" in fruit flies 2023-07-28T04:00:00Z When parthenogenesis happens, the egg cell in the female's body divides enough times it needs in order to create half the genes required to procreate. Why a crocodile’s ‘virgin birth’ isn’t a miracle 2023-06-10T04:00:00Z Although many invasive species are bigger and stronger than the locals, parthenogenesis is another factor that can contribute to their success. Crocodile’s ‘Virgin Birth’ Is a First for Science’s History Books 2023-06-09T04:00:00Z Asexual reproduction in animals occurs through fission, budding, fragmentation, and parthenogenesis. Concepts of Biology 2013-04-25T00:00:00Z After altering various combinations of genes, the scientists hit on a combination that induced parthenogenesis in roughly 11% of female fruit flies. ‘Virgin Birth’ Engineered into Female Animals for First Time 2023-08-01T04:00:00Z Sperling's paper expands scientific knowledge about parthenogenesis by showing there's a genetic component to it, instead of something being inherited. Fly-ing solo: scientists discover genetic on-switch for "virgin birth" in fruit flies 2023-07-28T04:00:00Z Through genomic sequencing, scientists found that the stillborn crocodile only contained genetic material from its mother, hence confirming parthenogenesis. Why a crocodile’s ‘virgin birth’ isn’t a miracle 2023-06-10T04:00:00Z Genetic testing technology that can identify parthenogenesis more readily is helping researchers discover that more and more species are capable of virgin births. Crocodile’s ‘Virgin Birth’ Is a First for Science’s History Books 2023-06-09T04:00:00Z The eggs can then turn into an embryo without being fertilized, in a process known as parthenogenesis. ‘Game changer.’ Scientists are genetically engineering crops to clone themselves 2023-05-17T04:00:00Z Some of the offspring of these genetically engineered flies were also capable of parthenogenesis. ‘Virgin Birth’ Engineered into Female Animals for First Time 2023-08-01T04:00:00Z Sperling said she is excited to see what other scientists do with this information, and how it spurs interest in the topic of parthenogenesis. Fly-ing solo: scientists discover genetic on-switch for "virgin birth" in fruit flies 2023-07-28T04:00:00Z In fact, a deeper look as to why parthenogenesis can happen is something less celebratory, in addition to how sustainable it is long-term. Why a crocodile’s ‘virgin birth’ isn’t a miracle 2023-06-10T04:00:00Z As parthenogenesis occurs in the birds and crocodiles, it is possible that dinosaurs had virgin births too. Crocodile’s ‘Virgin Birth’ Is a First for Science’s History Books 2023-06-09T04:00:00Z Some animals are able to reproduce asexually by a process called parthenogenesis. Biology for AP Courses 2022-06-09T00:00:00Z Some had three sets of chromosomes, whereas eggs laid by mothers reproducing through parthenogenesis usually have only two. ‘Virgin Birth’ Engineered into Female Animals for First Time 2023-08-01T04:00:00Z The offspring of D. melanogaster were also able to reproduce by parthenogenesis. Fly-ing solo: scientists discover genetic on-switch for "virgin birth" in fruit flies 2023-07-28T04:00:00Z In 2015, scientists found that 3 percent of a critically endangered sawfish population in Florida were conceived through parthenogenesis. Why a crocodile’s ‘virgin birth’ isn’t a miracle 2023-06-10T04:00:00Z The process, known as parthenogenesis, allows them to make more of their species when mates are scarce or absent. 15 Conservation Issues to Watch in 2022 2021-12-30T05:00:00Z Some vertebrate animals—such as certain reptiles, amphibians, and fish—also reproduce through parthenogenesis. Biology for AP Courses 2022-06-09T00:00:00Z “Parthenogenesis is the most effective way to reproduce. In animals, doing sex is very complicated,” says Tanja Schwander, an evolutionary biologist at the University of Lausanne in Switzerland, who has studied parthenogenesis in stick insects. ‘Virgin Birth’ Engineered into Female Animals for First Time 2023-08-01T04:00:00Z In a paper published last week in the Journal of Heredity, the scientists said parthenogenesis has been observed in condors for the first time. California condors almost went extinct. Now, scientists say, they are capable of reproducing without males. 2021-11-05T04:00:00Z As the scientists of the crocodile paper explained, what was once considered rare, parthenogenesis has now been documented across multiple vertebrate lineages. Why a crocodile’s ‘virgin birth’ isn’t a miracle 2023-06-10T04:00:00Z Before the findings made public on Thursday, the other known instances of parthenogenesis among birds were limited to turkeys, finches and domestic pigeons, according to the San Diego Zoo Wildlife Alliance. Endangered California Condors Can Reproduce Asexually, Study Finds 2021-10-30T04:00:00Z Although more common in plants, parthenogenesis has been observed in animal species that were segregated by sex in terrestrial or marine zoos. Biology for AP Courses 2022-06-09T00:00:00Z The new work could also help biologists to understand the evolution of parthenogenesis itself, says Chau-Ti Ting, an evolutionary biologist at the National Taiwan University in Taipei. ‘Virgin Birth’ Engineered into Female Animals for First Time 2023-08-01T04:00:00Z Nevertheless, Ryder said the discovery raised the question of whether parthenogenesis occurred because the condor population had dwindled to such low numbers. California condors almost went extinct. Now, scientists say, they are capable of reproducing without males. 2021-11-05T04:00:00Z Now, since a crocodile has been shown to be able to pull this off, it could be that dinosaurs may have been capable of parthenogenesis as a survival mechanism, too. Why a crocodile’s ‘virgin birth’ isn’t a miracle 2023-06-10T04:00:00Z The final clue that these chicks had developed from parthenogenesis was the fact that both were male. Endangered California Condors Can Reproduce Asexually, Study Finds 2021-10-30T04:00:00Z However, after several years, as the queen begins to age, she produces some offspring asexually in a process called parthenogenesis. Biology for AP Courses 2022-06-09T00:00:00Z She hopes to determine whether other species of fly have genes for parthenogenesis similar to those in D. mercatorum; this could help her to piece together how the behaviour evolved. ‘Virgin Birth’ Engineered into Female Animals for First Time 2023-08-01T04:00:00Z The discovery that condors are capable of virgin births - formally called parthenogenesis or asexual reproduction - surprised scientists. California condors: Virgin births discovered in critically endangered birds 2021-10-29T04:00:00Z It’s the first report of asexual reproduction in California condors, although parthenogenesis can occur in other species, including sharks, honey bees and Komodo dragons. Study finds California condors can have ‘virgin births’ 2021-10-28T04:00:00Z In the past, parthenogenesis has been thought of as a somewhat desperate form of reproduction, occurring when females were in low-male populations or in environments with few members of their own species, Dr. Wisely said. Endangered California Condors Can Reproduce Asexually, Study Finds 2021-10-30T04:00:00Z Instead, the resulting female was born through a process known as parthenogenesis, when females produce an offspring on their own. Unique water dragon dies at zoo; was born without male contribution 2019-07-06T04:00:00Z Sperling notes that some agricultural pests use parthenogenesis to multiply quickly, amplifying their power to damage crops. ‘Virgin Birth’ Engineered into Female Animals for First Time 2023-08-01T04:00:00Z This sort of asexual reproduction, known as parthenogenesis, is a first for the species and provides new hope for their recovery. California condors: Virgin births discovered in critically endangered birds 2021-10-29T04:00:00Z In this case, each mother condor had previously bred with males, producing 34 chicks, and each was housed with a fertile male at the time they produced the eggs through parthenogenesis. Study finds California condors can have ‘virgin births’ 2021-10-28T04:00:00Z The condors in captivity, however, had been paired with males in an enclosure, yet still reproduced through parthenogenesis. Endangered California Condors Can Reproduce Asexually, Study Finds 2021-10-30T04:00:00Z It’s known as “facultative parthenogenesis,” said scientists at the zoo, meaning “she reproduced without contribution from a male.” ‘Life found a way’: The National Zoo welcomes a startling addition 2019-06-07T04:00:00Z In the United Kingdom, for example, a species of moth turned to parthenogenesis because of widespread use of pesticides that disrupt the male moths’ reproduction. ‘Virgin Birth’ Engineered into Female Animals for First Time 2023-08-01T04:00:00Z "We were not exactly looking for evidence of parthenogenesis, it just hit us in the face. We only confirmed it because of the normal genetic studies we do to prove parentage." California condors: Virgin births discovered in critically endangered birds 2021-10-29T04:00:00Z Anna, an 8-year-old anaconda at the New England Aquarium in Boston, used the extremely rare reproductive strategy called parthenogenesis, which resulted in two living baby anacondas, a press release from the aquarium said. 10-foot anaconda gives birth to two ‘clones’ without male in Boston aquarium 2019-05-24T04:00:00Z According to Dr. Ryder, the discovery of “virgin births” in such a closely monitored bird population is leading scientists to wonder whether more birds in the wild are reproducing through parthenogenesis than previously believed. Endangered California Condors Can Reproduce Asexually, Study Finds 2021-10-30T04:00:00Z First, parthenogenesis, a system of asexual reproduction usually found in insects, lizards and plants. Virgin births: is there something fishy about Mary the stickleback’s little miracles? 2019-02-20T05:00:00Z She hopes to study which policies and pest-management strategies could trigger pests to rely on parthenogenesis — knowledge that could help to keep pests in check. ‘Virgin Birth’ Engineered into Female Animals for First Time 2023-08-01T04:00:00Z It reproduces through the miracle of parthenogenesis, meaning a female scorpion simply generates copies of herself twice a year — no male participation required. Venomous yellow scorpions are moving into Brazil’s big cities—and the infestation may be unstoppable 2019-02-18T05:00:00Z This is only the second confirmed case of parthenogenesis in a green anaconda. 10-foot anaconda gives birth to two ‘clones’ without male in Boston aquarium 2019-05-24T04:00:00Z Another interesting aspect of parthenogenesis is that lethal genetic traits cannot be passed down from the mother. Endangered California Condors Can Reproduce Asexually, Study Finds 2021-10-30T04:00:00Z Here all males died out two millennia before, and women have managed to reproduce through a not very well explained process of parthenogenesis. What Can We Learn from Utopians of the Past? 2018-07-23T04:00:00Z Some species dabble in parthenogenesis: Komodo dragons, velvet worms, zebra sharks, New Zealand mud snails. Shell shock: why crayfish replicants are taking over 2018-02-07T05:00:00Z In another part of the study, a scientist in Madagascar examined how well the crayfish is able to multiply in the wild via parthenogenesis, a natural form of asexual reproduction. Mutant, all-female crayfish spreading rapidly through Europe can clone itself 2018-02-07T05:00:00Z It added to a study published in 2003 that found the species essentially reproduced through cloning, a process called parthenogenesis. Growing Population of Crayfish Has One Female Ancestor 2018-02-06T05:00:00Z How the first marbled crayfish gained the ability to reproduce through parthenogenesis is a mystery, says Lyko. Geneticists unravel secrets of super-invasive crayfish 2018-02-05T05:00:00Z But some sharks, rays, bony fishes, and reptiles don’t need sperm—they practice what's called parthenogenesis, or virgin birth. Virgin Birth, Double Uteri, and Other Wondrous Female Abilities 2017-08-12T04:00:00Z Well, in terms of evolution, parthenogenesis is much less common because, over the extreme long term, it doesn’t allow for as much adaptation through mutation. Shell shock: why crayfish replicants are taking over 2018-02-07T05:00:00Z Unlike most ants, the raider ants reproduce asexually, through parthenogenesis. Scientists create the first mutant ants 2017-08-10T04:00:00Z "Please use morally approved techniques like parthenogenesis and binary fission." Call for sex book ban at temples lined with erotic art - BBC News 2017-06-16T04:00:00Z These studies showed a stunning lack of genetic diversity, owing presumably to the species’ recent origin and ability to reproduce through parthenogenesis. Geneticists unravel secrets of super-invasive crayfish 2018-02-05T05:00:00Z The exact biological triggers for parthenogenesis are unknown, he adds. Virgin Birth, Double Uteri, and Other Wondrous Female Abilities 2017-08-12T04:00:00Z Stick insects reproduce by a process called parthenogenesis — without males. Stick insect helps scientists study how animals move. 2016-02-15T05:00:00Z They concluded that their findings represented the first cases of such parthenogenesis found in the wild. A Mother’s Ability to Reproduce All by Herself 2015-10-19T04:00:00Z "If nothing else, it's an interesting phenomena. Whether this is long-term storage or parthenogenesis, it's cool. Just another sign that nature works in mysterious ways." The Virgin Snake Gives Birth for a Second Time 2015-09-17T04:00:00Z This natural form of cloning is called "parthenogenesis" — and it isn't as complicated as it sounds. The Verge Review of Animals: the all-female whiptail lizard 2015-07-19T04:00:00Z The researchers were investigating sawfish inbreeding when they discovered seven, all healthy, born via parthenogenesis, about 3 percent of those examined. Scientists document Florida 'virgin births' of endangered sawfish 2015-06-01T04:00:00Z The authors are now trawling through publicly available genetic databases of other species to investigate whether parthenogenesis may be happening more widely. Sawfish escape extinction through 'virgin births', scientists discover 2015-06-01T04:00:00Z But the latest analysis estimates that nearly 4% of sawfish in a Florida estuary were born without any genetic contribution from a male, in a phenomenon known as parthenogenesis. Sawfish spawn without sex 2015-05-31T04:00:00Z Some species of sharks are also known to demonstrate parthenogenesis, in which the mother gives birth to genetic replicas of herself without involving a male at all. Long-Term Sperm: Shark Gives Birth 4 Years after Contact with Male 2015-01-28T05:00:00Z Female Komodo dragons, for instance, sometimes engage in parthenogenesis. The Verge Review of Animals: the all-female whiptail lizard 2015-07-19T04:00:00Z The eggs of the females hatch healthy female clones, a process known as parthenogenesis. The Strange Tale of a New Species of Lizard 2014-12-18T05:00:00Z “Sir. Is it true that the offspring produced by parthenogenesis almost always are female?” Variations : Nature : Nature Publishing Group 2014-05-27T04:00:00Z But it is not yet clear how common parthenogenesis is in the wild across species. Sawfish spawn without sex 2015-05-31T04:00:00Z Because the pup was a genetic combination of the mother and another shark, parthenogenesis could not have occurred, and a male had to have been involved at some point. Long-Term Sperm: Shark Gives Birth 4 Years after Contact with Male 2015-01-28T05:00:00Z If men are obsolete, then women will soon be extinct — unless we rush down that ominous Brave New World path where women clone themselves by parthenogenesis, as famously do Komodo dragons, hammerhead and pit vipers. It’s a Man’s World, and It Always Will Be 2013-12-16T15:51:06Z A little bit is better than nothing: the incomplete parthenogenesis of salamanders, frogs and fish. Life and times of the wild Axolotl 2012-12-31T01:15:03.023Z Found across North America and Eurasia, Daphnia species mostly reproduce by parthenogenesis. Slideshow: Virgin Birth Not So Miraculous in Animal Kingdom 2012-12-27T14:51:40Z If this is true, parthenogenesis might be most common in species that are on the verge of extinction. Sawfish spawn without sex 2015-05-31T04:00:00Z But here it occurs across a generation; all females reproduce asexually via a process called obligate parthenogenesis. Virgin snake births found in wild 2012-09-11T23:45:09Z “We still lack data to understand when and why facultative parthenogenesis happens in the wild,” says Watts. Virgin Births Seen in Wild Vipers 2012-09-12T19:45:09.353Z Scientists believe that facultative parthenogenesis is more common in some lineages such as reptiles and sharks. Virgin snake births found in wild 2012-09-11T23:45:09Z After several molts, these females will produce their own offspring by parthenogenesis. Slideshow: Virgin Birth Not So Miraculous in Animal Kingdom 2012-12-27T14:51:40Z Dulvy cautions that parthenogenesis will not be enough to save the smalltooth sawfish. Sawfish spawn without sex 2015-05-31T04:00:00Z The development of eggs asexually, that is, without uniting first with a male cognate, is termed parthenogenesis. Being Well-Born An Introduction to Eugenics 2012-05-22T15:16:53.140Z Warren Booth, a molecular ecologist at the University of Tulsa in Oklahoma, now reports the first known case of wild facultative parthenogenesis, publishing the today in Biology Letters. Virgin Births Seen in Wild Vipers 2012-09-12T19:45:09.353Z But here it occurs across a generation; all female reproduce asexually via a process called obligate parthenogenesis. Virgin snake births found in wild 2012-09-11T23:45:09Z Genetic analysis and laboratory experiments confirmed that the animals were reproducing through parthenogenesis. Slideshow: Virgin Birth Not So Miraculous in Animal Kingdom 2012-12-27T14:51:40Z They are of very great zoological interest on account of the peculiarities of their life-history—parthenogenesis being of normal occurrence among most of them. Encyclopaedia Britannica, 11th Edition, Volume 13, Slice 3 "Helmont, Jean" to "Hernosand" 2012-04-14T02:00:23.707Z It has been shown that in the artificial summer of a green-house, parthenogenesis may continue for four years. Herbert Spencer 2012-02-29T03:00:20.773Z Booth says that the finding removes the “prevailing dogma” that facultative parthenogenesis occurs only when females are isolated. Virgin Births Seen in Wild Vipers 2012-09-12T19:45:09.353Z Sometimes, however, the septum between the two halves of the cyst does not break down, in which case parthenogenesis occurs, each sporoblast developing by itself into a small spore. Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 5 "Greek Law" to "Ground-Squirrel" 2011-12-05T03:00:51.527Z In the case of many insects in which parthenogenesis occurs, the determination of sex depends upon fertilisation. The Biological Problem of To-day Preformation Or Epigenesis? The Basis of a Theory of Organic Development 2011-08-29T02:01:04.170Z Some zoologists are therefore of the opinion that the development of the gemmule is an instance of parthenogenesis—that is to say of an organism arising from an egg that has not been fertilized. Freshwater Sponges, Hydroids & Polyzoa 2011-06-25T02:00:17.833Z Artificial parthenogenesis, or life artificially produced, has been of interest only as it leads me to learn how the electric charges of ions affect life phenomena. The Universe a Vast Electric Organism 2011-06-09T02:00:22.450Z How far this may extend in the direction of more mature development is shown by what is known about parthenogenesis. Degeneracy Its Causes, Signs and Results 2011-05-02T02:00:17.657Z The extraordinary facts that have been discovered by Professors Steenstrup, Owen, and others, within a few years, respecting what they call alternate generation, or parthenogenesis, have been thought favorable to the hypothesis of development. The Religion of Geology and Its Connected Sciences 2011-02-28T03:00:28.890Z In some Insecta and Crustacea exceptional parthenogenesis occurs: a certain proportion of the eggs laid are capable of undergoing either the whole or a part of development parthenogenetically, e.g. Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 3 "Electrostatics" to "Engis" 2011-02-06T03:00:53.093Z What is meant by "Mendel law of heredity"?What is meant by the term parthenogenesis? A Guide for the Study of Animals 2011-01-18T03:00:14.913Z You can bring about parthenogenesis only by positive ions. The Universe a Vast Electric Organism 2011-06-09T02:00:22.450Z This power of parthenogenesis, however, cannot continue indefinitely without extinction. Degeneracy Its Causes, Signs and Results 2011-05-02T02:00:17.657Z The aphides illustrate parthenogenesis; hermaphrodite forms produced from eggs produce viviparous wingless forms, which again produce others like themselves, and thus multiply during summer, one individual giving rise to millions. The New Gresham Encyclopedia. Vol. 1 Part 2 Amiel to Atrauli Artificial Parthenogenesis.—The experimental parthenogenesis of Loeb and Delage consists in plunging the egg into a liquid other than sea water, and returning it again to its original medium. The Mechanism of Life Name some animal in which parthenogenesis commonly takes place.What is sex dimorphism? A Guide for the Study of Animals 2011-01-18T03:00:14.913Z We know further that a similar process, but much more highly developed, is possible in what is called parthenogenesis, or virgin-birth, which can only be explained as a survival of the early form. The Truth About Woman The biologic evidence from the experiments of Maupas on parthenogenesis, elsewhere cited, is seemingly supported by the results of animals breeding in-and-in. Degeneracy Its Causes, Signs and Results 2011-05-02T02:00:17.657Z But these degenerate and disappear if reproduction by parthenogenesis or budding is continued during several generations. The Sexual Question A Scientific, psychological, hygienic and sociological study On three-dimensional vidar rolls, he showed them live shots of what the laboratories were doing, what they were trying to do—in the insemination groups, the incubators, the ray-bombardment chambers, the parthenogenesis bureau. It's All Yours What really happens is that whenever alternative courses of action are called for, the individuality splits up and continues on two or more divergent planes, very much like the parthenogenesis of a unicellular animal ... The Doorway To-day we know that the peculiar behaviour of the hybrid Hieraciums is due to the fact that they normally produce seed by a peculiar process of parthenogenesis. Mendelism Third Edition More often we have unconscionable yarns about men without noses, or with only one eye, tailed men, solid-hoofed men, Amazons, and parthenogenesis. The Discovery of America Vol. 1 (of 2) with some account of Ancient America and the Spanish Conquest Here, the female cell or egg only reproduces itself exceptionally by parthenogenesis. The Sexual Question A Scientific, psychological, hygienic and sociological study The chief point of novelty in M. Bataillon's discovery is that we have now an experimental demonstration of parthenogenesis in a vertebrate animal, and in one so highly organised as the frog. More Science From an Easy Chair For purposes of convenience in thinking I have temporarily called this phenomenon "stereochemic parthenogenesis." Northern Nut Growers Association, Report of the Proceedings at the Seventh Annual Meeting Washington, D. C. September 8 and 9, 1916. Thinking that it was due to parthenogenesis I bagged clusters of pistillate blossoms, and although setting nuts they all dropped off which is typical of non-pollenization. Northern Nut Growers Association Incorporated 39th Annual Report at Norris, Tenn. September 13-15 1948 Then again, there are abnormal cases; sometimes there is parthenogenesis. Northern Nut Growers Association Report of the Proceedings at the Fifteenth Annual Meeting New York City, September 3, 4 and 5, 1924 Among the higher animals, the vertebrates and man, there is no reproduction without conjugation; no parthenogenesis or budding. The Sexual Question A Scientific, psychological, hygienic and sociological study The tadpoles and young frogs so produced are examples of what is called "parthenogenesis"—that is to say, virginal reproduction—reproduction without fertilisation by material derived from a male parent! More Science From an Easy Chair We were evidently dealing with an instance of parthenogenesis. Northern Nut Growers Association, Report of the Proceedings at the Seventh Annual Meeting Washington, D. C. September 8 and 9, 1916. A large part of Loeb's book is devoted to a description of the author's remarkable experiments in artificial parthenogenesis, and an attempt to show that they offer a complete explanation. Science and Morals and Other Essays The jimson weed is the first plant which has ever been reproduced by parthenogenesis. Northern Nut Growers Association Report of the Proceedings at the Fifteenth Annual Meeting New York City, September 3, 4 and 5, 1924 Consanguinity perpetuated is harmful to the species, in the same way as parthenogenesis, or indefinite reproduction by fission or budding. The Sexual Question A Scientific, psychological, hygienic and sociological study These are the chief cases of regular and natural parthenogenesis, but there are others which might be enumerated. More Science From an Easy Chair If you get parthenogenesis through two or three generations I presume that same peculiar feature of the original parent would become so intensified as to become a marked feature of the progeny. Northern Nut Growers Association, Report of the Proceedings at the Seventh Annual Meeting Washington, D. C. September 8 and 9, 1916. This forced parthenogenesis which I have described seems to be a phenomenon with which botanists are unfamiliar. Northern Nut Growers Association Report of the Proceedings at the Fifth Annual Meeting Evansville, Indiana, August 20 and 21, 1914 In all of these nuts it seemed to me we were probably dealing with parthenogenesis. Northern Nut Growers Association, Report of the Proceedings at the Fourth Annual Meeting Washington D.C. November 18 and 19, 1913 The parthenogenesis of the lower animals having ceased in the vertebrates, each sex is indispensable, not only to the preservation of species, but also to each conception or reproduction of the individual. The Sexual Question A Scientific, psychological, hygienic and sociological study This parthenogenesis has been noticed in several species. Our Common Insects A Popular Account of the Insects of Our Fields, Forests, Gardens and Houses It may have been that they had gone on by what we call parthenogenesis, and we had the children without the father, had the female parent only, the fatherless chinkapin. Northern Nut Growers Association, Report Of The Proceedings At The Tenth Annual Meeting. Battle Creek, Michigan, December 9 and 10, 1919 In ordinary parthenogenesis the fruit grows without any pollen influence at all. Northern Nut Growers Association Report of the Proceedings at the Fifth Annual Meeting Evansville, Indiana, August 20 and 21, 1914 I speak of the matter as parthenogenesis in advance of microscopic examination of the ovules,—which will be made next year; but parthenogenesis seems to be the most likely explanation. Northern Nut Growers Association, Report of the Proceedings at the Fourth Annual Meeting Washington D.C. November 18 and 19, 1913 It is a sort of absolute poetry, a poetry of detached waver and brilliance, a beautiful flowering of language alone—a parthenogenesis, as if language were fertilized by itself rather than by thought or feeling. Contemporary American Literature Bibliographies and Study Outlines The unbeliever starts from the other end, and as likely as not with the question: Is a case of human parthenogenesis credible? and this he would call going straight to the heart of the matter. Pascal's Pensées After moulting four times, the foundress produces, by parthenogenesis, a number of false eggs, which it fastens to the leaf-stalks and under side of the foliage. Falling in Love With Other Essays on More Exact Branches of Science Poulton suggests one, in the fact that parthenogenetic reproduction only occurs in isolated species, not in groups of related species; as this shows that parthenogenesis cannot lead to the evolution of new forms. Darwinism (1889) We can speak of parthenogenesis only when the embryo originates from a female gamete alone, i. e., without fusing of protoplasmic mass of the female gamete with protoplasmic mass of the male gamete. Northern Nut Growers Association, Report of the Proceedings at the Fourth Annual Meeting Washington D.C. November 18 and 19, 1913 In all the different forms of asexual reproduction from fission to parthenogenesis, the female may in this sense be said to exist alone and perform all the functions of life including reproduction. Taboo and Genetics A Study of the Biological, Sociological and Psychological Foundation of the Family This was after he had to admit their parthenogenesis. Herland From the beginning he was aware of this parthenogenesis of the soul, whose capacity to multiply by taking cuttings was equivalent to bringing forth young in this life without conception. The Road to Damascus The smaller eggs develop without fertilisation, by parthenogenesis, and become males. Hormones and Heredity In either case, then, whether with hybrids or in cases of parthenogenesis, the early death of the embryo is due to inability to recollect, owing to a fault in the chain of associated ideas. Life and Habit But let us return to that special form of her resistless intervention that we find in parthenogenesis. The Life of the Bee SILK-MOTHS. -domesticated, species of. -history of. -causes of modification in. -differences presented by. -crossing of. -disease in. -effects of disuse of parts in. -selection practised with. -variation of. -parthenogenesis in. The Variation of Animals and Plants under Domestication — Volume 2 Is it true that female Primula plants always produce females by parthenogenesis? More Letters of Charles Darwin — Volume 1 The ova developing by parthenogenesis and giving rise to males segment in the usual way, and all the cells both of soma and gametocytes contain only N chromosomes. Hormones and Heredity I wish some one would write a book about dreams and parthenogenesis—for that the two are part and parcel of the same story—a brood of folly without father bred—I cannot doubt. Erewhon Revisited The same idea that, before, in parthenogenesis, sacrificed the future of the hive to the unwonted multiplication of males, now sacrifices the male to the future of the hive. The Life of the Bee For this, if for no other reason, a brief consideration of the means of artificial parthenogenesis may be of interest to the student of evolution. Darwin and Modern Science I thought on the subject, but gave up investigating what had been observed, because the female bee by parthenogenesis produces males alone. More Letters of Charles Darwin — Volume 1 Some workers, indeed, are capable of parthenogenesis, and give birth to children who never had fathers. Kwaidan: Stories and Studies of Strange Things Briefly, he holds that parthenogenesis is due to the inheritance of a "remnant of spermatic virtue": when the "spermatic force" or "virtue" is exhausted fresh impregnation occurs. More Letters of Charles Darwin — Volume 1 The question may be raised whether the larvae produced by artificial parthenogenesis can reach the mature stage. Darwin and Modern Science It thus happens that the phenomena of artificial parthenogenesis are linked together with the phenomena of haemolysis which at present play so important a role in the study of immunity. Darwin and Modern Science |
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