Daily Archives: February 6, 2017

GENES that increase an individuals reproductive output will be preserved and spread from generation to generation. That is the process of evolution by natural selection. More subtly, though, in species that have the sorts of learnable, and thus transmissible, behaviour patterns known as culture, cultural changes that promote successful reproduction are also likely to spread. This sort of cultural evolution is less studied than the genetic variety, but perhaps that should change, for a paper published this week in Nature Ecology and Evolution, by Janet Howard and Mhairi Gibson of the University of Bristol, in England, suggests understanding it better may help to wipe out a particularly unpleasant practice, that of female genital mutilation.

FGM, as it is known for short, involves cutting or removing part or all of a females external genitaliausually when she is a girl or just entering puberty. Unlike male circumcision, which at least curbs the transmission of HIV, the AIDS-causing virus, FGM brings no medical benefit whatsoever. Indeed, it often does harm. Besides psychological damage and the inevitable risk that is associated with any sort of surgery (especially when not conducted in clinical conditions), FGM can cause subsequent obstetric complications and put a woman at risk of future infections. All these seem like good reasons why it would harm reproductive output and thus be disfavoured by evolution, whether biological or cultural. Yet the practice persists, particularly in parts of Africa and among migrant populations originating in these places. Ms Howard and Dr Gibson wanted to understand why.

To do so they drew on data from five national health surveys carried out in west Africa (specifically, Burkina Faso, Ivory Coast, Nigeria, Mali and Senegal) over the past ten years. These provided data on the FGM-statusmutilated or otherwiseof more than 60,000 women from 47 ethnic groups. That enabled Ms Howard and Dr Gibson to establish the prevalence rates of mutilation in each of these groups, and to search for explanations of any variation.

They first established formally what common sense would suggest is truethat the daughters of a mother belonging to an ethnic group where the practice is widespread are, themselves, more likely to have undergone mutilation than those of a mother not belonging to such a group. But there was more to the pattern of those results than mere correlation. The average rates of mutilation in the groups the researchers looked at tended to cluster towards the ends of the distribution, near either 0% or 100%, rather than being spread evenly along it.

In the argot of statistics, then, the distribution is U-shaped. This suggests something is pushing behaviour patterns away from the middle and towards the extremes. What that something might be is in turn suggested by the two researchers second finding: the consequences of mutilation for a womans reproductive output.

For convenience, Ms Howard and Dr Gibson defined a womans reproductive output as the number of her children still living when she reached the age of 40. Just over 10,000 women in the five pooled surveys were over this age, and it was from these that the researchers drew their data. Their analysis showed that in ethnic groups where mutilation was common, mothers who were themselves mutilated had more children over their reproductive lifetimes than did the unmutilated. In groups where mutilation was rare, by contrast, it was the other way around. At the extremes, in groups where mutilation was almost ubiquitous or almost unheard of, the average difference amounted to a third or more of an extra child per lifetime. That is a strong evolutionary pressure to conform to the prevailing social norm, whatever it is.

What causes this difference Ms Howard and Dr Gibson cannot say for sure, but they suggest that conforming to whichever norm prevails might let a woman make a more advantageous marriage, and also give her better access to support networks, particularly of members of her own sex. Cultural evolution, in other words, is generating conformity in the same sort of way that biological evolution does when, say, the plumage of a male bird has to conform to female expectations of what a male looks like if that male is to mate successfully, even though the particular pattern of his plumage brings no other benefit.

All this does, though, offer a lever to those who are trying to eradicate female genital mutilation, for unlike genetic norms, cultural ones can be manipulated. The distributions shape suggests that, if mutilation rates in societies where FGM is now the norm could somehow be pushed below 50%, then positive feedback might continue to reduce them without further effort (though such effort could well speed things up).

One thing that is known to push in the right direction is more and better educationand not just for girls. That is desirable for reasons far wider than just the elimination of FGM, however. In a companion piece to Ms Howards and Dr Gibsons paper, Katherine Wander of Binghamton University, in New York state, offers a thought inspired directly by the new research. She wonders if fostering social connections between cut and uncut women in a community might reorganise support networks specifically in a way that reduces the advantages of mutilation.

More widely, the method Ms Howard and Dr Gibson have pioneered, of looking for unanticipated reproductive advantages that help explain the persistence of other undesirable behaviours, might be applied elsewhere. So-called honour killings would be a candidate for such a study, as would the related phenomena of daughter neglect, and the selective infanticide and selective abortion of females. On the face of things these might be expected to be bad for total reproductive output. But perhaps, as with FGM, that is not always the case. And, if it is not, such knowledge would surely help in the fight against them.

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Cultural evolution and the mutilation of women - The Economist

Biological invasions pose major threats to biodiversity, but little is known about how evolution might alter their impacts over time.

Now, Rutgers scientists have performed the first study of how evolution unfolds after invasions change native systems.

Now, Rutgers scientists have performed the first study of how evolution unfolds after invasions change native systems.

The experimental invasions elaborate experiments designed by doctoral student Cara A. Faillace and her adviser, Professor Peter J. Morin took place in glass jars suitable for savory jam or jelly, with thousands of microscopic organisms on each side. After entering the jars uncharted territory the invaders won some battles and lost some against the natives.

Oftentimes, we know the initial impacts of invasive species but we dont know the long-term impacts if things will get better or worse, said Morin, a distinguished professor in the Department of Ecology, Evolution & Natural Resources in the School of Environmental and Biological Sciences. Cara found that both things can happen, and it will depend a lot on the details of the biology of the species thats introduced and the biology of the community thats invaded.

The Rutgers scientists coauthored a study Evolution Alters the Consequences of Invasions in Experimental Communities that was published recently in Nature Ecology & Evolution.

Typically, biological invasions unfold when humans introduce exotic species either accidentally or on purpose into areas where they are not native, Faillace said. Invasive species, a subset of exotic species, usually are ecologically or economically harmful.

Rutgers doctoral candidate Cara A. Faillace in the Morin Lab.

In their study, the Rutgers researchers compared the performance of populations of resident and invading species before and after they interacted, and potentially evolved, for about 200 to 400 generations. They used two different groups of resident species consisting of aquatic bacteria, ciliates protozoans with hair-like projections called cilia and rotifers, organisms with cilia-laced mouths and retractable feet. The ciliates and rotifers were collected from Bamboo Pond in Rutgers Gardens in New Brunswick.

For the nearly two-year experiments, one species from each group was designated as an invader of the other community. One group had five ciliates and a rotifer. The other group had three different ciliates and a different rotifer.

The organisms worlds were loosely lidded 8.5-ounce jars about the size of a jelly jar. The jars contained food, vitamins, sterile water and two sterile wheat seeds for extra nutrients.

There were likely hundreds of thousands of protozoans in a microcosm, or jar, and populations turned over fairly quickly, with many chances for mutations, Morin said.

Every time an individual divides, its still alive and it takes six to 24 hours for most of these organisms to reproduce, he said.

Peter J. Morin, distinguished professor in the Department of Ecology, Evolution & Natural Resources.

A couple of species were abundant in the beginning but went extinct (they could not be found in the jar) after being invaded, Faillace added.

In nature, most biological invasions are accidental, Morin said.

It took several tries to get the European starling in North America established, and that was intentional, he said. Now theyre the bane of every native bird.

Gypsy moths were brought to North America by someone who wanted to see if they could establish a silk industry using gypsy moths, Morin said. The cage they were kept in was damaged, they were released and the rest is history.

Yet many organisms, such as the emerald ash borer, which kills ash trees, get introduced accidentally through commerce, Faillace said. They include the Asian longhorned beetle, which also attacks and kills trees and likely arrived in shipping containers or pallets.

Biological invasions are especially damaging when a predator or pathogen is introduced and when native species have never encountered a predator, the scientists said.

Climate change is a major factor in biological invasions and its impact is likely increasing, Faillace said.

Presumably as climate shifts, the species that can invade will change or the ranges of species that have invaded will change, she said.

The bottom line is that we should expect to see changes in the impacts of invasive species as invaders and native species evolve over time, Morin said.

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How Evolution Alters Biological Invasions - ScienceBlog.com (blog)

A reconstruction of Calvapilosa, showing what this primitive mollusc most likely looked like in real life. Photograph: Jakob Vinther/Model made by Esben Horn (10tons.dk)

Lumpy, hairy and with a nail-like horny patch it sounds like a hobbits toe. In fact, its a portrait of what researchers say the common ancestor of slugs, snails and squid might have looked like.

The surmise is based on the discovery of the fossilised remains of a mollusc, thought to have lived about 480 million years ago, which has short spines all over its body and fingernail-like shell over its head which housed a radula a tongue-like structure found only in molluscs with more than 125 rows of teeth.

Believed to be a very early ancestor of a group of marine molluscs known as chitons, the discovery, scientists say, suggests that the common ancestor of all molluscs likely had a similar appearance.

I would say that our animal probably is very close to the spitting image of how the ancestor of all molluscs must have looked like 530 million years ago, said Jakob Vinther, a molecular palaeobiologist from the University of Bristol and co-author of the research published in the journal Nature.

The newly discovered animal is believed to have reached up to 12cm in length although the juvenile found in the Yale collection is less than 2cm long. Its name, Calvapilosa kroegeri, is a reference to the hairy shell that covered its head together with a nod to Bjrn Krger. The palaeontologist spotted a complete version of the fossilised creature among a drawer of recently collected Moroccan rocks at Yale University almost a decade after the first incomplete fossil was found.

We had been looking through those drawers to try and see if there were any specimens and we missed it, said Vinther. [Then Krger said] Why dont you guys use this specimen it is entirely complete, and then he pulled this thing out and it was like dude, that is totally what we needed!

The discovery also sheds light on a previously discovered fossils, revealing that a number of older creatures whose nature had been debated due to a lack of preserved details were also molluscs, due to their similarity in structure to the newly discovered creature. We could bring all these other fossils into the fold of thinking [about] molluscan evolution, said Vinther.

It also reveals that an type of early animal with two shell-like plates, known as Halkieria, was also a mollusc. Despite Halkeria being older, the authors suggest that the number of plates grew during evolution, leading to modern day chitons, which bear a row of eight plates on their back. Basically our animal sits right at the base of the branch that leads to chitons, said Vinther.

With a very early non-molluscan creature called Wiwaxia known to have had scales and spikes, the researchers go further, proposing an evolutionary path in which the common ancestor of all molluscs bore spines, a single plate, and a radula before a variety of branches emerged, eventually giving rise to molluscs as diverse as snails, clams and slugs.

Martin Smith, an invertebrate palaeontologist at the University of Durham who was not involved in the research, described the new find as exciting. This is a really important fossil, he said. Theres been a lot of discussion about the common ancestor of molluscs and of course there is such a wide diversity of body plans of molluscs today ranging from squids to snails to slugs and various other things that it is very hard to work out what their common ancestor looked like.

While it has previously been suggested that the common ancestor was shell-less, the new study, says Smith, points towards a single shell and a radula forming part of the body plan of molluscs, which have since been lost, modified or multiplied in various branches over the course of evolution. It completely transforms how we see the earliest history of molluscs and how we read the fossil record, said Smith of the new find.

But Julia Sigwart of Queens University Belfast, cautioned against such an interpretation, saying that even at 480 million years old, the newly-discovered fossil is too young to draw conclusions about what the common ancestor of all molluscs would have looked like.

This is not a particularly old fossil in the context of molluscan evolution, she said. But, she added, the fossil does show how many different forms existed through the history of molluscs over the last half billion years. Any time we find these exceptionally preserved fossils, they are very important for us to understand what the body plans looked like, because the fossils are so rare.

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Lumpy, hairy, toe-like fossil could reveal the evolution of molluscs - The Guardian

This week, Feb. 6 10, The University of Southern Mississippi will host a series of activities in honor of Charles Darwins birthday.

Many universities and institutions will be celebrating Darwin Day on Feb. 12, which is a day to promote science education and, in particular, Darwins contributions to biology. Southern Miss has extended its day-long celebration to a week. There will be a fossil hunt, lectures, video screenings, socials, a panel discussion and a keynote address through the University Forum by famous paleontologist Neil Shubin, a professor at the University of Chicago and author of Your Inner Fish.

Some of you may be offended that we are having a celebration of Darwin. In fact, in just the last two months, Ive been bombarded on Facebook by accusations of undermining the religious faith of our students by teaching a theory based on little fact with the ultimate desire of implementing a liberal agenda and atheism in our society. That is far from the truth I dont try to undermine anyones faith, Im fairly moderate politically and Im not even an atheist! I would like to challenge our students, particularly Christians who may feel that evolution has implications for their religious faith, to consider a few key points and then join us for some of the activities this week.

First, we are celebrating Darwin because his ideas have had a substantial impact in biology and even in the other sciences. His work did not just resolve the question of whether species were individually created about 6,000 years ago. Rather, his work has impacted science at many levels: Antibiotic resistance, relatedness and migration of human populations, lactose tolerance, emerging diseases and vaccine production, pesticide resistance and even forensic science and software engineering.

Evolution has impacted public policy, too, from fishing regulations to control of invasive species and conservation biology. Evolution is a broad explanation that includes more than just biology. If you reject evolution, you are also rejecting much of geology, chemistry and anthropology. In other words, you are rejecting science.

Second, there are plenty of religious reasons why one can believe in evolution in addition to the overwhelming scientific evidence in its favor. Even St. Augustine, who lived from 354 430 A.D., argued long before Darwin that a literal reading of Genesis was inappropriate. There are plenty of nonliteral texts in the Bible, and one has to determine the intent of those passages based on context and language. Given the words used and the different versions of creation, a literal reading of Genesis 1 2 is not faithful to the text itself.

For example, the Hebrew word adam can also refer to man or mankind, and the passages talk about how God speaks to the waters to bring forth certain kinds of life and speaks to the land to bring forth other kinds of life, poetically paralleling evolution. Man even comes from the dust of the ground. Many major Christian denominations today (e.g., Roman Catholics, Episcopalians, Lutherans, Methodists) have stated that evolution and Christian religious faith are not mutually exclusive. Even the man who gave us the famous quote, Nothing in biology makes sense except in the light of evolution, Theodosius Dobzhansky, was actually a devout Russian Orthodox Christian.

Finally, many people even the loosely religious think that evolution is lacking (or outright wrong) because it seems improbable and reduces us humans to the outcome of chance. Many scientists have actually made this problem worse, because they use words like blind, purposeless and undirected.

Well, science doesnt deal with purpose in this sense (we dont think of stochastic events as either blind or seeing, and chance doesnt do anything), and the use of those words reflects more of the materialistic worldview of the authors. However, we do know that mutations are random with respect to natural selection; two men won the Nobel Prize for demonstrating that in 1969. A Christian, except for those who dont believe in (ontological) chance at all, need not worry: There are plenty of beautiful examples of where randomness or unpredictability at one level is deterministic at another level.

When you flip a (fair) coin, you cant be sure whether it will land on heads or tails. However, if you flip one million coins, you can be quite confident that very close to 50 percent will land on heads and 50 percent will land on tails. The opposite is true, too, where deterministic dynamics at one level lead to unpredictable behavior at another. Famous examples of this are often called chaos, where the tiniest of changes in a predictable framework result in unpredictable patterns. You may have heard of the butterfly effect; a butterfly flapping its wings in Brazil can lead to a tornado in Texas.

Evolution is a fascinating subject. Dont be afraid of it ( reflexive hostility, as Kenneth Miller calls it), and be willing to challenge your (or your pastors or your parents) deep reservations about it, because you want to live a life of integrity, a life of unity, where your faith whatever it be and your knowledge fit together seamlessly. When I teach evolution, I give students a survey at the beginning of the course. One of the questions I ask is, What is the first word that comes to mind when you hear the word evolution? When I first began teaching evolution at USM about 10 years ago, common answers were controversy and religion. These days, the most common answer is dinosaurs. Thats a great sign.

For those with doubts, I have several recommendations. For a book that clearly lays out the scientific evidence for evolution but that also deals with religious (particularly Christian) issues, I highly recommend Kenneth Millers book Finding Darwins God: A Scientists Search for Common Ground between God and Evolution (1999). If youre interested in the improbability, I suggest David Bartholomews God, Chance and Purpose: Can God Have It Both Ways? (2008) and (the non- and even perhaps anti-religious) book by David Hand, The Improbability Principle: Why Coincidences, Miracles, and Rare Events Happen Every Day (2015). All of these books are available in the USM library.

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USM Darwin Day: 'Genesis' a parallel to evolution - The Student Printz

Ivanka Trump 'Feels Terrible' for Insensitive Gala Photo Nordstrom Drops Ivanka Trump's Line Ivanka Trumps Baby Theodore Crawls for First Time in the White House

If we could turn back time actually, we have! Ivanka Trump, the newly minted first daughter of President Donald Trump, has been in the limelight her whole life, which means we've watched her grow up. See her beauty evolution in the video above!

From a rosy-cheeked teen with a rosebud mouth (circa 1998) to a platinum-blonde student and model in the early aughts, to a sleek entrepreneur with a glamorous but understated makeup palette, the former Trump Organization VP has transformed right before our eyes.

Today, Ivanka, who first launched her eponymous brand in 2007 with fine jewelry, is now a mom of three children (with fellow real estate mogul husband Jared Kushner), but she's just as polished as ever.

"I keep my makeup minimal at the office, but that's also because I like to spend my time with my children in the mornings, and that tends to come at the expense of doing my makeup," Ivanka told Who What Wear in 2014. "That being said, I think that bright lipstick can work well, as long as the rest of your makeup is minimal."

Words she clearly lives by! Watch Ivanka's beauty transformation now.

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Ivanka Trump's Beauty Evolution, From 1998 to Today Watch - Us Weekly

Inside Higher Ed

Tracking the Evolution of Student Success Inside Higher Ed College administrators in the field of student success who feel as though their jobs are getting more hectic each day aren't imagining things, according to the EAB. Researchers at the EAB marked the Washington, D.C., based research and consulting firm ...

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Tracking the Evolution of Student Success - Inside Higher Ed