Is sex necessary? Virgin birth and opportunism in the garden by David Quammen
Author: David Quammen
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BIRDS DO IT, BEES DO IT, or so goes the tune. But the songsters, as usual, would mislead us with drastic oversimplifications. The full biological truth happens to be more eccentrically nonlibidinous. Sometimes they don’t do it, those very creatures, and get the reproductive results anyway. Bees of all species, for instance, are notable for their ability to produce offspring while doing without. Birds mostly do mate, yes, but at least one variety—the Beltsville Small White Turkey, a domestic breed out of Beltsville, Maryland—has achieved scientific renown for a similar feat. What we’re talking about here is celibate motherhood, procreation without copulation, a phenomenon that goes by the name parthenogenesis. Translated from the Greek roots: virgin birth.
He explains what parthenogenesis is by using examples.
The author gives a good over view of what the article will be discussing in more depth. He gives the reader a rundown of what they will be reading about.
The writer grabs the readers attention with a phrase most likely known by the reader, the birds and the bees.
Quammen begins with an exceptionally attention-catching phrase that most readers would quickly recognize as a reference to sex
Most brilliant writers start off their stories by getting their reader’s attention in the first paragraph by sharing an interesting fact or so called a hook. Quammen begins his story with a hook that pulls his readers in because they are curios what else he has to say in his essay.
The author references the “birds and the bees” talk, which is commonly connotated with sex. This gives the reader a general idea of the broader subject this explanatory essay falls under.
As a subject the idea of parthenogenesis might not seem interesting nor understandable. The author uses the transitions, topic sentences, and summaries to help the reader understand a pretty alien topic to the general public. It also helps to lighten up the technical terminology of the subject.
Early on, the author defines the main topic of the essay, helping the reader go into the essay with some context. The author also uses an array of examples scattered through the essay to help demonstrate the ideas he is talking about.
This little segment of the paragraph immediately grabs the attention of the reader because its odd to think of birds and bees having sex. Makes you want to read more.
By starting with a well-known saying, Quammen grabs the reader’s attention and makes them feel in the loop.
This saying engages the readers interest, because this saying is familiar to the reader. It allows the reader to connect to the article.
The author challenges the readers common view of what sex and reproduction look like and how they go hand in hand.
This helps the reader better understand how Quemmens idea fits into reality.
In this part of the article, he gives multiple examples of how sex is necessary. One of the examples he uses is bees.
Helps to keep the flow of the essay while also keeping the attention of non-catholics, alluding to an explanation of why anyone can believe in this.
the author paraphrased and gave background information about his topic
Quammen uses sentences such as this one to show readers where he’s going with his essay. Doing so helps clearly communicate the information to readers.
Telling the reader early on what the essay will be about.
And you don’t have to be Catholic to believe in this one.
This section adds humor to the passage and makes the reader more interested.
Quammen breaks up two large paragraphs chalk-full of big words and complex concepts with a humorous line.
I’m not offended by this, but I also don’t think it’s that funny. I feel the article is really calling out an entire religion almost giving them a bad rep. I know that the Catholic church doesn’t have the most liberal view on sex, but that’s not altogether bad. Sex can have bad effects on people depending on their experiences and it isn’t for everyone. Because of this, I feel like he’s trying to gain the readers interest, but I don’t think he’s going about it in the best way.
Miraculous as it may seem, parthenogenesis is actually rather common throughout nature, practiced regularly or intermittently by at least some species within almost every group of animals except (for reasons still unknown) dragonflies and mammals. Reproduction by virgin females has been discovered among fishes, amphibians, birds, reptiles,* crustaceans, mollusks, ticks, the jellyfish clan, flatworms, roundworms, segmented worms; and among insects (notwithstanding those unrelentingly sexy dragonflies) it is especially favored. The order Hymenoptera, including all bees and wasps, is uniformly parthenogenetic in the manner by which males are produced: Every male honeybee is born without any genetic contribution from a father. Among the beetles, there are thirty-five different forms of parthenogenetic weevil. The African weaver ant employs parthenogenesis, as do twenty-three species of fruit fly and at least one kind of roach. Gall midges of the species Miastor metraloas are notorious for the exceptionally bizarre and grisly scenario that allows their fatherless young to see daylight: M. metraloas daughters cannibalize the mother from inside, with ruthless impatience, until her hollowed skin splits open like the door of an overcrowded nursery. But the foremost practitioners of virgin birth—their elaborate and versatile proficiency unmatched in the animal kingdom—are undoubtedly the aphids.
Here the author goes through and gives examples of multiple different species that reproduce through parthenogenesis. The author is illustrating the idea of the vast number of species that do produce either regularly or intermittently by parthenogenesis.
In this section, Quammen sets forth a readable plan for his readers. He gives a main idea and brief explanation of what he will be going into more detail later on in the article.
the topic sentence gives a foreshadowing the the explanation of the pervasiveness of parthenogenesis in nature.
While the author doesn’t use a lot of sources, the few he does use illustrate the points he is trying to demonstrate. The author seems to have a wide understanding of the subject and doesn’t need to integrate too many sources to make his essay convincing. He weights more heavily in facts that can be confirmed by a basic search.
I’d say the author is only partially successful in engaging the reader. The reprieves from the blocks of information are few and far between.
The author continues to introduce the topics that he talks about later in the article.
Seems to lead with normalizing parthenogenesis, continuing to familiarize the term to the readers
In the beginning of the paragraph the author continues to introduce the parthenogenesis ideas to the readers so that they can get a better understanding of the topic.
This gives me the ability to picture some of the examples of species who can partake in parthenogenesis.
the author does a really good job of introducing information that is a proven fact, and connecting it to his opinion. I think he did a really good job keeping the information and his opinion seperate.
This sentence is really helpful for explaining and bringing this topic into context because it adds a lot of examples of where this occurs in nature.
The author does not use many quotations or siting within the text to integrate sources. He simply lays out the facts as if to be common knowledge. In this sentence specifically, the author paraphrases about the parthenogenesis of the African weaver and then quickly moves on.
This is a very interesting sentence that could be written many different ways, but the author of the article was able to use word choice to paint a picture of how Gall Midges are born.
Quammen makes use of transitional sentences to further guide readers and maintain a sense of flow throughout the essay. Including things like transition makes information more easy to follow.
Now no sensible reader, not even one who has chosen this book, can be expected to care much, I realize, about aphid biology qua aphid biology. But there’s a larger reason for dragging you into the subject. The life cycle of these nebbishy insects, the very same that infest rosebushes and houseplants, exemplifies not only how parthenogenesis works but also, very clearly, why evolution has devised such a reproductive shortcut.
This paragraph is a really good way to engage the reader because it breaks the fourth wall and actually includes the reader in the conversation by recognizing what they may be thinking.
Paragraph four is a great example to show others how to engage readers into the topic they are trying to explain. And what I thought was interesting was the author includes the reader in the conversation therefore makes it personal and makes the reader connect with the essay.
By relating to the reader’s possible feelings, the author helps to maintain the reader’s interest.
he has explained what parthenogenesis and and now this sentence helps transition the reader to the “why does this matter” portion of the essay
Quammen presents a lot of complex information, so explaining WHY it’s important keeps readers interested and avoids confusion.
Quammen mentions where aphids are commonly seen in our daily lives to allow the reader to visualize the insects.
First, the biographical facts. A typical aphid, which feeds entirely on plant juices tapped from the vascular system of young leaves, spends winter as an egg, dormant and protected. The egg is attached near a bud site on the new growth of, say, a poplar tree. In March, when the tree sap has begun to rise and the buds have begun to burgeon, the egg opens and an aphid hatchling appears, promptly plugging its sharp snout into the tree’s tender plumbing. This solitary individual aphid will be, necessarily, a wingless female. If she is lucky, she will become sole founder of a vast aphid population. Having sucked enough poplar sap to reach maturity, she produces (by live birth now, not egg-laying, and without benefit of a mate) daughters identical to herself. These wingless daughters also plug into the tree’s flow of sap, and they also produce wingless daughters—whose daughters produce more daughters, geometrically more, generation following generation until sometime in late spring, when crowding becomes an issue and that particular branch of that particular tree can support no more thirsty aphids. Suddenly there is a change: The next generation of daughters are born with wings. They fly off in search of a better situation.
This begins to explain parthenogenesis
This seems to be a summary in the form of paraphrasing. I would venture that he took out a lot of the difficult scientific jargon to make the scientific facts easier for the average reader.
I would assume that in order to explain it scientifically, it would be very confusing to most. So, the author paraphrases a lot of it in order to allow the readers to understand better.
very clear cut topic sentence laying out the contents of the paragraph.
This gives some additional context into how this process takes place.
This sentence is summarizing the main points about the topics the author wants to get across by using outside context and facts to support.
One such aviatrix lands on a herbaceous plant—a young climbing bean, say, in someone’s garden—and the pattern repeats. She plugs into the sap ducts on the underside of a new leaf, commences feasting, robbing the plant of its vital juices, and then delivers by parthenogenesis a great brood of wingless daughters. The daughters beget more daughters, those daughters beget still more, and so on, until the poor bean plant is encrusted with a dense population of these fat little sisters. Then again, neatly triggered by the crowded conditions, a generation of daughters are born with wings. Away they fly, looking for prospects, and one of them lights on, say, a sugar beet. (The switch from bean to beet is possible for our species of typical aphid, because it is not a dietary specialist committed to only one plant.) The sugar beet before long is covered, sucked upon mercilessly, victimized by a horde of mothers and nieces and granddaughters. Still not a single male aphid has appeared anywhere in the lineage.
the author makes the separation between the information and his opinion clearly separate but it still flows.
This idea helps define the process of parthenogenesis and shows the effect of this process, which is the fact that there are no male aphids in the lineage.
The author splits up the topics with techniques to keep it interesting like humor or more personal writing styles.
The lurching from one plant to another continues; the alternation between wingless and winged daughters continues. Then, in September, with fresh and tender plant growth increasingly hard to find, there comes another change.
This is beginning to compare two different things and explore more strategies
The readers can assume that the female aphids will find mates but the writer hasn’t explained this yet. The reader is curious to know how when and why they will find mates so continues reading. The author set this up really smart to keep readers engaged.
Flying daughters are born who have a different destiny: They wing back to the poplar tree, where they give birth to a crop of wingless females unlike any so far. These latest girls know the meaning of sex! Meanwhile, at long last, the starving survivors back on that final bedraggled sugar beet have brought forth a generation of males. The males too have wings. They take to the air in search of poplar trees and first love. Et voilà. The mated females lay eggs that will wait out the winter near bud sites on that poplar tree, and the circle is closed. One single aphid hatchling—call her the matriarch—in this way can give rise in the course of a year, from her own ovaries exclusively, to roughly a zillion aphids.
Well and good, you say. A zillion aphids. But what’s the point of it?
In some cases the reader might be wondering a few things and have a few questions om the topic. When the author uses Rhetorical questions in his/her writing, and that happens to be the same question the reader has, it sparks interest in the reader and they are encouraged to keep reading.
This group of sentences keeps readers on track with all of the information presented. It forecasts what’s to come in the essay to avoid confusion.
By asking a question that many readers may have, the author captures more interest.
Asking a so what question was a good way to transition. It gets the reader thinking about the information but also thinking about how all that information is relevant before they are told how it’s relevant. This was also a good way to keep the reader engaged.
Again, the author addresses the audience with a question which is a good way to keep their focus
Up to this point the writer has droned on about what the subject is and now he is trying to tell the reader why they should care and how it applies on a wider spectrum.
The author understands that the topic can be boring and pokes fun at it all while transitioning the essay to why people should care
The point, for aphids as for most other parthenogenetic animals, is 1) exceptionally fast reproduction that allows 2) maximal exploitation of temporary resource abundance and unstable environmental conditions, while 3) facilitating the successful colonization of unfamiliar habitats. In other words, the aphid, like the gall midge and the weaver ant and the rest of their fellow parthenogens, is by its evolved character a hasty opportunist.
This paragraph defines the reasoning behind aphids and what they are good for.
This summarizes the relevance of this topic and gives a more concise meaning to parthenogenesis.
This is a term of science, not of abuse. Population ecologists make an illuminating distinction between what they label “equilibrium species” and “opportunistic species.” According to William Birky and John Gilbert, from a paper in the journal American Zoologist: “Equilibrium species, exemplified by many vertebrates, maintain relatively constant population sizes, in part by being adapted to reproduce, at least slowly, in most of the environmental conditions which they meet. Opportunistic species, on the other hand, show extreme population fluctuations; they are adapted to reproduce only in a relatively narrow range of conditions, but make up for this by reproducing extremely rapidly in favorable circumstances. At least in some cases, opportunistic organisms can also be categorized as colonizing organisms.” Birky and Gilbert emphasize that the potential for such rapid reproduction is “the essential evolutionary ticket for entry into the opportunistic life style.”
Helps us understand the difference between opportunistic and equilibrium species.
In this paragraph, Quammen uses a very long quote for the purpose of getting a specific definition into the piece. He wants to capture the exact wording of the definition that the journal American Zoologist. I would speculate that Quammen felt that he needed the scientific and specific definition to get the point across as clearly and accurately as possible.
the author utilized quotation marks to clearly state the proper name of what he was describing.
Quamman introduces new vocabulary that isn’t that common and follows it up with an explanation that is a direct quote from someone else.
The author proposes the vocabulary necessary to further his point. He then introduces a source that he used in order to explain such vocabulary, then he goes on explaining what the point of the quote was.
The author quotes the American Zoologist journal to help explain the difference between equilibrium species and opportunistic species.
The author uses a quotation here to emphasize an idea, and give validity to what he is saying.
And parthenogenesis, in turn, is the greatest time-saving trick in the history of animal reproduction. No hours or days are wasted while a female looks for a mate; no minutes lost to the act of mating itself. The female aphid attains sexual maturity and, bang, she becomes automatically pregnant. No waiting, no courtship, no fooling around. She delivers her brood of daughters, they grow to puberty and, zap, another generation immediately. The time saved by a parthenogenetic species may seem trivial, but it is not. It adds up dizzyingly: In the same duration required for a sexually reproducing insect to complete three generations for a total of 1,200 off-spring, an aphid can progress through six generations (assuming the same maturation rate and the same number of progeny per litter) to yield an extended family of 318,000,000.
In this paragraph I believe the author tries to change the wording of the paragraph to help the reader engage better but it isn’t very effective.
Helps us visualize how many more offspring can be produced through parthenogenesis
Even this isn’t speedy enough for some restless opportunists. That matricidal gall midge Miastor metraloas, whose larvae feed on fleeting eruptions of fungus under the bark of trees, has developed a startling way to cut further time from the cycle of procreation. Far from waiting for a mate, M. metraloas does not even wait for maturity. When food is abundant, it is the larva, not the adult female fly, who is eaten alive from inside by her own daughters. And as those voracious daughters burst free of the husk that was their mother, each of them already contains further larval daughters taking shape ominously within its own ovaries. While the food lasts, while opportunity endures, no Miastor metraloas female can live to adulthood without dying of motherhood.
The implicit principle behind all this nonsexual reproduction, all this hurry, is simple: Don’t pause to fix what isn’t broken. Don’t tinker with a genetic blueprint that works. Unmated female aphids, and gall midges, pass on their own genotypes virtually unaltered (except for the occasional mutation) to their daughters. Sexual reproduction, on the other hand, exists to allow genetic change. The whole purpose of joining sperm with egg is to shuffle the genes of both parents and come up with a new combination that might perhaps be more advantageous. Give the kid some potent new mix of possibilities, based on a fortuitous selection from what Mom and Pop individually had. Parthenogenetic species, during their hurried phases at least, dispense with this genetic shuffle. They stick stubbornly to the genotype that seems to be working. They produce (with certain complicated exceptions) natural clones of themselves.
But what they gain thereby in reproductive rate, in great explosions of population, they lose in flexibility. They minimize their genetic variability—that is, their options. They lessen their chances of adapting to unforeseen changes of circumstance.
Which is why more than one biologist has drawn the same conclusion as M.J.D. White: “Parthenogenetic forms seem to be frequently successful in the particular ecological niche which they occupy, but sooner or later the inherent disadvantages of their genetic systems must be expected to lead to a lack of adaptability, followed by eventual extinction, or perhaps in some cases by a return to sexuality.”
Because of how Parthenogenesis occurs, there will be more offspring in the immediate future, but the distant future can propose problems because of lack of adaptability.
The author quotes M.J.D White to help support the conclusion.
In this paragraph, the author reports the causes and effects of Parthenogenetic forms, and states what the final outcome is.
Quamman ends it all with an outside opinion that seems to be a summary of what M.J.D. White has to say. I would say that this was one of the most effective of the document because it had the best flow
The author uses a direct quote for two main reasons in this section. First, he wants to add scientific credibility to what he is saying and second, he believes that it is important for the reader to get this exact wording. I think he specifically wanted to get in the part about “return[ing] to sexuality” because it bolsters his argument.
the author did a good job of citing the quote
This paragraph holds one of the only quotations. He quotes M.J.D by comparing his conclusion with the one given. By explaining his views first, the following information is expected and therefore flows rather smoothly.
concludes with a quote which solidify his claim that sex is a necessary thing
So it is necessary, even for aphids, this thing called sex. At least intermittently. A hedge against change and oblivion. As you and I knew it must be. Otherwise, surely by now we mammals and dragonflies would have come up with something more dignified.
By ending the article on a humorous tone, the author makes his/her writing stick out in the minds of the readers.
This paragraph ties everything together, making Quammen’s writing make perfect sense. It’s the final “road sign.”
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Throughout the entire document, the author spits out a plethora of information without bringing attention to the fact that he had to do extensive research in order to obtain this information. His formatting makes it sound as if these facts are more like common knowledge.
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