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Book Review: The Red Queen: Sex and the Evolution of Human Nature by Matt Ridley
(out of 5 stars)
Matt Ridley presents his arguments for the development of sexual reproduction through a variety of insights in The Red Queen. Much like the world in which Alice met the character referred to in the title, Ridley's approach is jumbled, disjointed, and too raggedly-paced to enjoy fully.
Ridley bases his thoughts on strong evolutionary arguments, such as those for sexual selection, arms races, and symbiogenesis. For the purely biological discussion, this works quite fine. However, as Ridley moves into human sociological and cultural points, which take up most of the book, he loses the narrative and often slips in assumptions which are either unproven or have (since publication in 1994) turned out to be wrong. This, combined with a ragged flow of thoughts and chapters which only marginally relate to each other, leaves the reader with a less-than-enthusiastic support for Ridley's thesis.
Still, there is much to glean in Red Queen, and Ridley certainly gets his facts in order when discussing biological aspects. Readers new to the subject should pick up some interesting tidbits, but should also update their knowledge with more recent works by Richard Dawkins and others. Ridley's later book Genome is much better written and presented, and is recommended to anyone who enjoys this book or wants to delve into genetics and disease. Three and one-half stars.
Book Review: The Making of the Fittest: DNA and the Ultimate Forensic Record of Evolution by Sean Carroll
(out of 5 stars)
Molecular biologist Sean Carroll presents an outstanding, deeply scientifically satisfying look at the forensic evidence for evolution in The Making of the Fittest. By focusing his argument on the very smallest bits of evidence, Carroll provides an amazing look into the world of the cell and DNA which leaves the reader with little doubt that evolution and natural selection are clearly capable of developing the entities and processes we find in nature today.
Starting off with a look at bloodless cold-water fish, Carroll jumps into the nature of adaptive mutations. Moving on, he shows that, given time and large numbers, the "miracles" of evolution are practically inevitable, even if not specifically predictable in every detail. Carroll demonstrates that some genes are nearly "immortal", lasting nearly unchanged for millions of years. Further, he explores how old genes and their proteins are frequently repurposed into new uses.
From there, the book moves into fossil genes which allow researchers to trace changes in lineages, as well as the fact that evolution tends to favor the production of similar results even if the affected genomes are not related. Carroll wraps up by showing that humans and other complex entities can be produced by the power of DNA, natural selection, mutation, and drift.
A great follow up to Carroll's previous work on evolutionary development, Fittest is a fascinating glimpse into the world of microbiological detectives. Highly recommended to anyone with an interest in biology and evolution. Four and one-half stars.
Book Review: Genome: The Autobiography of a Species In 23 Chapters by Matt Ridley
(out of 5 stars)
Matt Ridley's Genome is an exploration of human chromosomes heavy in biological and physiological science. Ridley, a journalist and science writer, looks at each chromosome per chapter, using a gene or two found on each to discuss a different aspect of physiology or behavior as affected by the gene, its alleles, or its mutated variations. A strong effort for any reader interested in biology and genetics, Genome is a treat from the very beginning.
Ridley manages to pack a lot of details into the book despite concentrating each chapter on one or two specific genes on the featured chromosome. He themes each chapter on concepts such as Love, Instinct, Conflict, and Free Will, using research on a gene to show how these concepts are affected by genetics.
This book is comprehensive and contains a lot of cutting-edge science from the time of publication (1999), but it remains approachable to the popular science reader. The examples Ridley chooses are fantastic and offer the reader information about research into molecular biology, physiology, psychology, behavior, neurochemistry, anthropology, and many other subjects.
All in all, a wonderful book filled with still-relevant scientific information. Any biology or popular science reader should enjoy Ridley's pace and presentation, and there is a great deal to learn about how genes affect a wide range of concepts. Four and one-half stars.
Book Review: The Greatest Show on Earth: The Evidence for Evolution by Richard Dawkins
(out of 5 stars)
There are few authors alive capable of weaving wonder and authority into popular science writing better than Richard Dawkins, and in his newest book The Greatest Show on Earth: The Evidence for Evolution, released in September, 2009, he has shown that he is still the master of popular biology. Following a narrative that works much as the one employed by Charles Darwin in On the Origin of Species (and frequently mentioning Darwin), Dawkins presents a comprehensive look at the modern state of evolutionary theory, and more specifically, the evidence which proves it is true beyond any serious doubt.
I had read many Dawkins books prior to Greatest Show, including his biology and science-oriented books The Selfish Gene, The Extended Phenotype, Unweaving the Rainbow, The Blind Watchmaker, and River Out of Eden. I have not yet read The Ancestors Tale (which I understand is Dawkins most comprehensive biological work, nor have I read Climbing Mount Improbable (which Dawkins has stated is his own favorite work), both of which I own but have yet to get to. So, my review is in light of these experiences (or lack thereof).
The first couple of chapters are for softening up any hesistant readers and convincing new learners that evolution is not only realistic, it can be observed around us in a myriad of ways, including the comparisons between natural selection and the artificial selection practiced by human animal and plant breeders.
Following this intro, Dawkins lays down the tool kit and shows how Neo-Darwinian theory knows how to trust estimated dates, looking at the various chemical clocks available.
The chapter titled "Before Our Very Eyes" was the most enjoyable and enlightening for me, personally, as the reader has described for him/her several fascinating experiments which have demonstrated the power of natural selection and mutation to drive complex genetic progression. The information on the Richard Lenski-led study of E. coli is worth the price of the book alone. Tremendously important and strong evidence for Dawkins' central thesis.
Dawkins follows this by moving into fossil records, showing the reader how scientists have studied and come to see the fossil record as important, but not the most important facts available to evolutionary theory. He shows that the 'gaps' in the fossil record are actually useful for taxonomic reasons, and posits that a complete fossil record would lead to immense confusion when trying to determine just where a new species begins from the old. Dawkins also knocks down the argument that talk of 'missing links' is useful, and pleads for the cessation of this term since its usefulness has long-since been destroyed. Like he says often, every fossil we find is a missing link, every one is a transitional fossil of some sort.
The chapter "You did it yourself in nine months" was my least favorite, though it was certainly necessary to present in a comprehensive view of evolution. The following chapter on biogeography returns to a superior narrative and offers strong evidence for geographic proof of evolution, again, just as Darwin did in describing the variety of species found strew across the Galapagos Islands. Following that are chapters on cousinship among life forms and the ability of DNA to provide a historical archive which begin to draw together a personal closeness that derives from the evidence of the preceding chapters.
The final couple of chapters move a bit more toward being meditative, though don't expect Dawkins to get too mushy. What begins as a discussion of arms races ends with a look at 'evolutionary theodicy', where Dawkins argues that we find suffering and pain exactly as we would expect from the emotionless processes of natural selection.
Finally, the book winds down with more reflection as Dawkins expounds upon the last paragraph of Darwin's Origin and draws together the book's conclusion by reinforcing that the fact of evolution does not depend on any statement about abiogenesis or origin of life concerns. Clearly, what the theory suggest, and has been proven by practically every bit of evidence uncovered, is that, however it started, evolution is the way in which living things grow, compete, reproduce, and change.
I haven't read a more comprehensive book on Evolution to date, and I think Dawkins has abolutely knocked it out of the park here. I admit to a strong Dawkins bias, so I wanted to like this book, but I also had very high hopes for it because it was the first Dawkins biology-centric book to be released since I started reading his work. I expected a ton. I got it and more.
For the beginning reader, I would still recommend the much-more streamlined arguments in Jerry Coyne's Why Evolution is True, but for the reader with some science experience, or for the curious reader who wants the full picture, this is as good as it gets. Five stars.
How a Lancet Fluke Comes to Commandeer an Ant, Perhaps
This is an essay I wrote for a science course which describes a plausible natural selection scenario for how a parasitic lancet fluke evolves to be capable of a neurochemical 'mind control' of an ant host. I am not a professional scientist, so I claim no expertise on these subjects. The post to which I am responding was made by a fellow student, and was a response to an earlier post I made in a discussion of environment and responsibility. Here, I am countering a statement that my references to the lancet fluke (more info here: http://www.ted.com/talks/dan_dennett_on_dangerous_memes.html ) and the fish-tongue-eating-crustacean known as Cymothoa exigua (more info: http://www.youtube.com/watch?v=vAlEfrwr8aU ), which he refers to as "two horrifying examples", demonstrate that "nature [is] out of balance, or is a battle of Good-vs.-Evil? Perhaps even an unsettled balance of natural selection, due to our negligence of humans disrupting nature's preservation?." My rebuttal follows, edited for typos, and with off-topic text removed.
As to the 'two horrifying examples', I would argue that neither example is one of an out-of-balance nature nor a battle of good-vs-evil. Neither appears to be affected at all by human activity. The lancet fluke, for instance, is not alone in its ability to take over another creature in some useful way, there are literally countless examples like this one. Nature simply favors any ability which gives a member of the species an advantage over others of its species, and by extension, sees advantages in species which are generally better adapted than other species competing for the same resources -- which should not be confused with group selection, a concept which is controversial and outside the mainstream in biology, though there are absolutely well-respected biologists holding positions in favor of group selection, but I digress.
Let me create a hypothetical progression of lancet fluke behavior. This is purely a mind exercise with few details and backed only by my readings in biology and behavior, but I think it serves us well and presents a plausible pathway, even if incorrect and flawed in real details. Also note that when I use singular terms, such as 'fluke', I'm referring to a statistically signficant set of flukes acting in some way or possessing some characteristic, and am not suggesting that a single specific fluke was responsible for each stage.
The lancet fluke, like all parasites, requires a host, and we know that the first cycle in the fluke's existence takes place in the body of a snail ("Dicrocoelium dendriticum"). Originally, it is easy to imagine a life cycle that saw the fluke exist completely within the snail, and there are countless parasites for which this model is quite typical.
However, natural selection will favor any genetic change which gives an advantage over other members of the species, even if that edge is very small. Imagine, then that the snail spits up a slime ball which contains living lancet flukes. (Snails do in fact do this and theory holds that this is a likely vector taking the lancet fluke into the ant's body ("Dicrocoelium dendriticum")). The ant, which either physically contacts or otherwise ingests the slime ball, becomes a secondary host for any members of the fluke species which can survive and reproduce during this second stage. Initially, this was probably only a bare few, but enough flukes possessed the ability to live in the snail, survive in the slime ball, and then live in the ant's body that this ability was strongly favored by natural selection to the exclusion of the flukes which could not do so. ***
So, now we have a fluke which has evolved a survival trick which extends its life and offers it an advantage which allows it to reproduce and pass down genes which also tend to favor this trick. Again, this isn't anything inherently good or bad, and certainly didn't require human intervention, this is really the way natural selection works. It is cold, without emotion, and without forethought. It is simply a process which rewards (without intent) any advantage to survival possessed in the genes of a replicating entity. The fluke which survived the slime ball stage and took advantage of the ant-body stage was more likely to reproduce than one which died in the ant's body, and given that this survival had a large reliance on genetics, was also more likely to produce offspring which could likewise take advantage of the ant-body stage.
From there, you can imagine that ants are regularly eaten by ruminants such as cows and sheep. Ants crawl all over grass and other delicacies enjoyed by grazers, so it is inevitable that large numbers are swallowed by such beasts. Natural selection again gives pressure: if any fluke was capable of surviving in the gut of a cow, that fluke was again more likely to reproduce offspring capable of doing the same.
So at this point, we have a fluke which has gone from living solely in the belly of snail to a naturally-selected subset that was capable of surviving the snail coughing it up in a slime ball, being swallowed by an ant, and then being swallowed by a cow. We haven't yet gotten to the 'mind control' ability, but that comes next.
Given that this fluke has now a genetic advantage, however small, over other flukes and over other competing species, it may appear well off. But natural selection does not offer species many opportunities to rest. Likely, the snail, ant, and cow bodies have experienced pressure to be able to survive this invasion. Any fluke infestation which killed its host too soon probably didn't live long enough to reproduce (and likewise, neither did the host). This fatality-condition is shared by both fluke and host genes. Any combination which resulted in death for the pre-reproductive fluke or host whittled down the combination of fluke and host genes which were selected for, and only those flukes with genes which allowed the host to survive and reproduce while also allowing itself to suvive and reproduce enjoyed significant advantage over those which did not, in terms of leaving offspring.
Imagine, then, that the ant develops a set of defenses against the fluke. Perhaps natural selection favors ants which are less likely to position themselves somewhere they might be grazed upon. Perhaps behaviors which result in staying low to the ground or holding along the edge of fields (rather than in the middle of them) would find these ants less likely to be eaten. Naturally, this is bad news for the fluke which, by now, rather expects to get on with its third stage of life in the belly of the cow.
So here comes one of the amazing parts of natural selection: its ability to derive complex and apparently abstract behavior out of a few basic rules. Differential survival means that any advantage, no matter how small, is enough for the process of natural selection to reward these small advantages with the ability to leave more offspring. Imagine that a line of flukes possess a mutation which allows it to secrete a chemical trigger to the ant which prevents the (newly developed, in evolutionary time) behavior which has protected the ant from being eaten as often by cows. We don't need to posit that there was intent here, perhaps various mutations in the fluke had occurred which generated different chemical excretions. We only care hear about the one that actually affected the behavior of the ant in a way advantageous to the fluke.
Suddenly, the fluke has pressured the ant to change its behavior, and the ant is now more likely to return to its original behavior, or demonstrate a new behavior, which left it more likely to be eaten by a cow. This sort of chemical triggering is well-documented and I won't go into details here, except to mention that bacterial and viral infections use all manor of chemical triggers to affect a myriad of things. Again, there doesn't need to believe this is done with intent. For every thousand mutations which change the way chemicals are produced by a parasite, perhaps only one will ever have anything other than a neutral (or negative) effect on its host. This variety, between parasites which possess this one-in-a-thousand mutation and those which do not, is all natural selection needs to differentiate between them. If the chemical allowed its possessors to survive and reproduce more frequently, it is straightforward to see that this would be an advantage that future generations were more likely to possess. The fluke never needed to plan this devious trick, it was just along for the ride built by its own (marginally, but significantly) superior genes and subjected to pressure from natural selection.
The last step here is just an extension of the previous. Once a chemical trigger is in place which advantaged flukes being able to produce it, it is just a short distance to chemical triggers which directed the ant to repeatedly climb the blade of grass. The process is the same as above, so I won't repeat it here.
And so, we've looked at an entirely plausible explanation for how natural selection would deliver a lancet fluke capable of 'mind control' over an ant, living originally only in the belly of a snail, but evolving a complicated adaptation which saw it survive several stages of life in hosts from snail to ant to cow. I'll not go into the tongue-eating-crustacean situation since it too would have gone through a process mirroring this one.
Again, there is no need to posit intent or 'good vs bad', this is just the way natural selection works. Harsh, cold, or heartless, perhaps, but those really are human concepts which we anthropically apply to the world around us.
I'll not get into the 'reason for human existence' since that is a teleological subject probably best left alone here (and to avoid any heated emotions from all of us who have our beliefs or lack-there-of). I am, however, completely in agreement with you about reducing the toxins we dump, and I hope that rational and reasonable people, maybe even ourselves, can study and implement strategies which do just that.
References:
Wikipedia. (n.d.) Wikipedia - Dicrocoelium dendriticum. Retrieved on October 2, 2009 from http://en.wikipedia.org/wiki/Dicrocoelium_dendriticum
*** as a digression, natural selection doesn't necessarily produce an all or nothing differential survival, as Darwin himself explained in On the Origin of Species. The hypothetical situation described above might find that one species of lancet fluke, which evolved from the original species found only in snails, evolved adaptations which required life cycles in both snail and ant, while a second species evolved, also from the original species, which did not. This process works again at the point in which the fluke moved into a third stage in a ruminant body. Differential selection is a manner in which species are not only selected for, but the fuels the divergence of species from their common ancestry.
Book Review: Before the Dawn: Recovering the Lost History of Our Ancestors by Nicholas Wade
(out of 5 stars)
Science journalist Nicholas Wade has delivered an exploration of human genetics in the spirit of Jared Diamond's Guns, Germs, and Steel. Wade works backwards in time, using genetic clues to discover knowledge about prehistoric human societies. Before the Dawn offers a breadth of knowledge about current genetic research into human populations and migrations, and draws some fascinating conclusions about the rise and dispersal of early human societies.
Wade's narrative largely follows research into genetic variations found in the Y chromosome and in mitochondrial DNA. These variations, the distribution of which allows researchers to track common ancestry and branching, are used to narrow the likely periods of human movement out of Africa to points beyond. A bit of time is spent on the earliest culturally modern humans in Africa before moving on latter periods of migration and settlement. Potential interactions with hominid relatives is discussed, as is the impact of various cold spells and ice ages.
Wade explores social behavior as well, showing how researchers have applied darwinian natural selection and genetic drift to account for both universal and isolated behaviors. Later, language is considered, with significant caveats as to its effectiveness in signalling fundamental shifts in human population. The discussion on race is well crafted. Wade does not bow to social pressure in describing genetic variations found among the races, including a fascinating discussion of the intellectual prowess of Ashkenazi Jews. Just to be clear, Wade is not advocating superiority of any race, he wants only to point out that there are significant data indicating genetic differences of isolated human populations can produce measurably different abilities.
I found Before the Dawn to be fascinating, and would highly recommend it to anyone who enjoyed the Pulitzer Prize-winning Guns, Germs, and Steel. Wade may not be a scientist, but he has conducted a thorough investigation into the ongoing research of population genetics and offers the reader a tremendous treat of science and history. Five stars.
Book Review: Unweaving the Rainbow: Science, Delusion, and the Appetite for Wonder by Richard Dawkins
(out of 5 stars)
Richard Dawkins has a knack for writing popular science books which offer poetic descriptions of the grand expanses and microscopic details. In Unweaving the Rainbow, Dawkins takes on the notion that science can be quite literally poetic. The book's title comes from the notion put forward by poet John Keats that Isaac Newton destroyed the beauty of rainbows by explaining its form. Dawkins turns that notion around and shows that the beauty and poetry of nature are greatly enhanced by explaining the details.
This wide-ranging book includes a strong mix of popular science (including biology, chemistry, astronomy, anatomy, and zoology) as well as Dawkins' characteristic philosophical thoughts. Unweaving demonstrates to the reader that the wonder of science is not that it destroys the beauty of nature, but that it allows us to gain an even greater appreciation for that beauty. From the nature of starlight and genetics to the ways in which humans are deceived by those claiming supernatural 'facts', Dawkins constantly expresses his awe of the natural world.
The latter parts of the book are centered on genetics and philosophy of mind. Here, of course, Dawkins is in his comfort zone, and the reader who has not read the authors' biology-centered books such as The Selfish Gene will explore some of the amazing characteristics of evolution and DNA. Experienced readers of Dawkins' works won't find much new information in this section, but should read it anyway since Dawkins incorporates a philosophy of science that is often skipped in the more clinical studies.
Unweaving the Rainbow is simply one of the very best widely-accessible popular science books out there. The discussion of coincidence is fantastic and should open the eyes of a reader who had never considered probabilities in this way. While it would help to have some exposure to science writing prior to picking up this book, Dawkins is very careful to introduce the nature of science softely and with much poetic contemplation. One of the best introductions to a wide-range of scientific thought and philosophy and very highly recommended to science readers at all levels. Four and one-half stars.
Book Review: The Blind Watchmaker by Richard Dawkins
(out of 5 stars)
Having read The Selfish Gene, The Extended Phenotype, and The God Delusion by Dawkins, I had been collecting the rest of his books to read at some point. The Blind Watchmaker is Dawkins' comprehensive look at the the evidence for evolution and proof that no designer need be posited in order to understand and explain biological diversity. The book itself is outstanding until you get to the last three chapters, which, for me, were not as pleasing an argument for Dawkins' thesis in the book's subtitle: Why the evidence of evolution reveals a universe without design.
Dawkins is a master at explaining highly complicated biological ideas in a popular science manner. Watchmaker starts off with excellent arguments for the emergence of complexity from less complex characteristics. Arguing that there indeed are examples of 'good design', Dawkins describes echolocation in bats and other animals to show how the appearance of design is strong. He then goes on to show how this appearance of design is not actually backed by the evidence.
Further chapters describe the nature of DNA, and how it provides an 'archive' of historical instructions. Dawkins emphasizes that evolution works as a cumulative selection process (a significant point often missed or ignored by anti-Darwinian advocates). In the chapter dealing with origins, Dawkins' explanation for one possible description of abiogensis (involving imperfections in the crystalline structure of clay) shows that we don't need to posit supernatural beings to have some notion of how life can form from non-life (and to be clear, as Dawkins is in this chapter, this hypothesis is NOT being advocated as the abiogenic solution, only that it is one reasonable scenario that could potentially lead to life).
Once Dawkins gets to chapter 9, however, the book loses some focus as the author attempts to counter scholaraly arguments of his peers. He tackles the problems of punctuationism, a chapter which largely argues above the reader's head and toward Dawkins' fellow scholars. The next chapter, dealing with competing theories of taxonomy, while interesting, are not needed at all to support the book's thesis. The last chapter follows this trend and again provides no real support for the development of Dawkins' thesis. This chapter also suffers from now being scientifically out of date (written in the mid 1980s). Embryology has made massive progress in developing theories and understanding of development (leading to the term 'evo devo' to describe evolutionary development), leaving this last chapter unfulfilling two decades after it was penned.
Blind Watchmaker is fascinating argument in favor of Darwinian evolution by means of natural selection, and the first eight chapters are especially enjoyable. The last three chapters drag the book down a bit and leave a rather unsatisfied ending to this otherwise fantastic exploration of evolution. Still, Watchmaker is well worth the read. I eagerly await Dawkins' forthcoming book The Greatest Show on Earth, which I expect will be an updated and expanded version of this work. Four stars.
Book Review: Why Evolution is True by Jerry Coyne
(out of 5 stars)
Creationists have long maintained that the evidence in favor of evolution consists of a few fossils open to a variety of interpretations. Biologist Jerry Coyne shatters that argument with this fascinating look at the mountains upon mountains of evidence in favor of evolution. Not only has Coyne shown the reader the myriad of ways in which the processes of evolution work their magic, he shatters the creationist argument that we cannot witness evolution in our own time.
The book begins with an excellent description of evolutionary theory, a much needed explanation for creationists who repeatedly demonstrate that they have no idea what the theory even predicts. From there, Coyne moves into fossil records and how they help us understand past events in evolution. Coyne is very clear in showing that evolutionary theory has testable predictions which can be made, all of which are verified by the results we find in the fossil record.
Vestigal organs, embryonic development, and poor 'design' are shown to prove beyond a doubt that evolution has affected every life form. Following that, Coyne explores the contributions of biogeography to show that evolutionary predictions are confirmed as accurate by the distribution of life across the continents.
Evolution is then explored as an engine, and a whole chapter is dedicated to the role of sex in the process. Speciation, a concept that creationists clearly do not understand, as predicted by evolutionary theory, is confirmed in every way by various observations and experiments. Humans get special attention as Coyne shows yet again how humans share evolutionary origins with all life.
As Coyne points out, every single piece of evidence ever found fails to contradict the predictions made by evolutionary theory, and practically all of the evidence clearly supports evolution. No observation or experiment has ever presented data which could not be explained by evolution, contrary to the propaganda being spread by creationists. Not only is there no debate among scientists about the fact of evolution, there is absolutely no evidence at all that any old or alternative explanation holds any water in explaining the data.
This book serves as the current source for explaining the evolutionary theory and the arguments in favor of it. Coyne's writing is easy to read, and while he includes science from many disciplines, the typical popular science reader should have no trouble comprehending his points. Coyne stays away from specifically attacking the religious arguments and instead concentrates on making his case for evolution. Excellent book, timely topic, and an outstanding, detailed summary of the fact that evolution is real and explains the broad processes behind the life we see around us. Five stars.
Mammals See Genome Shrink After Dinosaurs
Evidence buried in the chromosomes of animals and plants strongly suggests only one group -- mammals -- have seen their genomes shrink after the dinosaurs' extinction. What's more, that trend continues today, say Indiana University Bloomington scientists in the first issue of a new journal, Genome Biology and Evolution.
The scientists' finding might seem counter-intuitive, given that the last 65 million years have seen mammals expand in diversity and number, not to mention dominance in a wide variety of ecological roles. But it is precisely their success in numbers that could have led to the contraction of their genomes.
"Larger population sizes make natural selection more efficient," said IU Bloomington evolutionary biologist Michael Lynch, who led the study. "If we are correct, we have shown how to bring ancient genomic information together with the paleontological record to learn more about the past."
And the present. Lynch says the data he and his colleagues analyzed suggest human genomes are still undergoing a contraction -- though you shouldn't expect to see noticeable changes in our chromosomes for a few million years yet.
Lynch's group examined the genomes of seven mammals, eight non-mammalian animals and three plants, specifically with regard for the long terminal repeat (LTR) sequences of transposable elements, a curious sort of "jumping" genetic sequence initially dropped into genomes by viruses. IU School of Informatics (Bloomington) bioinformaticians Mina Rho and Haixu Tang oversaw the survey of mammalian and non-mammalian genomes.
