Feeds:
Posts
Comments

Posts Tagged ‘evolution’

Photo: Photobucket at Psychology Today
Hadza grandmother in Northern Tanzania. Hazda grandmothers’ labor and care is correlated with better nutritional status and survival rates in Hadza children. Anthropologist Kristen Hawkes studies the Hazda for a window on ancient worlds.

As a grandmother myself, I am naturally drawn to well researched articles on grandmothers throughout history. Their role has fluctuated, of course. In some periods, they have been useful — essential even. At other times, they have been pretty useless. Here’s a report from John Poole about very early grandmothers. I heard it at Rhode Island Public Radio.

Kristen Hawkes is an anthropologist at the University of Utah. She tries to figure out our past by studying modern hunter-gatherers like the Hadza, who likely have lived in the area that is now northern Tanzania for thousands of years. Groups like this are about as close as we can get to seeing how our early human ancestors might have lived.

“Over many extended field visits, Hawkes and her colleagues kept track of how much food a wide sample of Hadza community members were bringing home. She says that when they tracked the success rates of individual men, ‘they almost always failed to get a big animal.’ … In this society at least, the [old] hunting hypothesis seemed way off the mark. If people here were depending on wild meat to survive, they would starve.

“So if dad wasn’t bringing home the bacon, who was? After spending a lot of time with the women on their daily foraging trips, the researchers were surprised to discover that the women, both young and old, were providing the majority of calories to their families and group-mates.

“Mostly, they were digging tubers, which are deeply buried and hard to extract. The success of a mother at gathering these tubers correlated with the growth of her child.

But something else surprising happened once mom had a second baby:

“That original relationship went away and a new correlation emerged with the amount of food their grandmother was gathering. …

“In this foraging society, it turns out, grandmothers were more important to child survival than fathers.”

Other researchers have come up with other likely benefits of prehistoric grandmothers.

Michael Tomasello is a developmental psychologist at Duke University and the Max Planck Institute. … Tomasello originally assumed that the pro-social traits in human babies [described by researchers such as U.C. Davis primatologist Sarah Hrdy] were preparing kids for skills they’d need as adults, in line with the Man the Hunter hypothesis. Now he thinks that Hrdy’s proposal – that human babies are so socially oriented as a result of shared child care and feeding – is a more compelling theory. The traits appear so early in a human’s life that it makes better sense that they were adapted to early childhood situations rather than adult hunting behaviors.

“It’s this ability to ‘put our heads together,’ as Tomasello puts it, that may have allowed humans to survive, thrive and spread across the globe. While the men were out hunting, grandmothers and babies were building the foundation of our species’ success – sharing food, cooperating on more and more complex levels and developing new social relationships.”

More.

Read Full Post »

The artist I have in mind is four. Here are some watercolors he painted over a couple days at Christmas.

The Christmas tree is green along the left side, but this artist likes lots of color. He is careful to keep colors from running together and getting muddy.

He paints snowmen and people in twos.

The still life features a banana, apples, grapes, a pear and limes.

I love that over two days, his people evolved to have hair, arms and a discernible smile. I’m smiling, too..

123016-xmas-tree

https://suzannesmomsblog.files.wordpress.com/2016/12/123016-snowmen.jpg

 

 

 

 

 

 

 

123016-still-life-with-fruit

123916-evolution-of-figure-painting

Read Full Post »

Here’s something fun from the bird kingdom: a mating dance that looks like Michael Jackson’s moonwalk and a researcher who posits an aesthetic sensibility in animals.

WNYC radio in New York has the story.

Richard Prum is an ornithologist at Yale University … Some of Prum’s latest work is on the philosophy of aesthetics. It stems from his earliest research, as a young scientist, studying small South American birds called manakins. Manakins are known for outlandish mating displays. The males perform an elaborate dance, including moves that look a lot like moonwalking.

“To Prum’s eye, the diversity and complexity of these dances could only be explained as an appeal to the birds’ aesthetic preferences — in other words, it’s art. ‘My hypothesis is that ornament in manakins evolves merely because it’s beautiful,’ Prum says.

“This idea clashes with the view of most evolutionary biologists, who see displays like these as signs of evolutionary fitness. They think the male manakin’s dance signals to females that he is healthy and will sire strong offspring. …

“Prum says that Charles Darwin was on his side. ‘That was Darwin’s original idea about mate choice — it’s about the aesthetic faculty’ …

“Doesn’t this idea about animals having aesthetic preferences anthropomorphize them? ‘I think that we don’t anthropomorphize birds enough!’ Prum says. ‘We’re afraid of talking about their subjective experiences, because we can’t measure it. But in fact, what they experience is desire, the subjective experience of beauty, of being attracted to something.’ ” More here.

Video: NatGeoWild

Read Full Post »

“How did the turtle get its shell?” asks Carolyn Y. Johnson in the Globe.

“A group of scientists at Yale University and the Smithsonian Institution argue that a reptile fossil that has been gathering dust in museum collections is actually a turtle ancestor, and that its reduced number of ribs, distribution of muscles, and T-shaped ribs could help settle the question once and for all.

“In a paper published Thursday in the journal Current Biology, they unveil the argument that a 260 million-year-old creature called Eunotosaurus africanus was a turtle ancestor, hoping to help resolve a debate that has split the scientific community for decades. …

“The ink spilled so far has roughly divided the scientific community in two camps. On one side are those who believe that the turtle shell came about as external bony scales, similar to the ones found on armadillos or certain lizards, that eventually fused together with the reptile’s internal rib cage. On the other side are those who believe that reptiles’ ribs instead began to broaden until they eventually formed the bony protrusion that is the shell, mirroring the way that turtles develop in the egg.”

Which theory does the 260-million-year-old Eunotosaurus support? Read up.

“ ‘The results are pretty convincing; previously I was skeptical as to whether Eunotosaurus was a likely relative of turtles,’ [Kenneth Angielczyk, a paleobiologist from the Field Museum in Chicago], wrote in an e-mail. ‘But Tyler [Lyson]’s results make me think it is a plausible idea.’  ”

Scientists clearly have a lot of fun, but let me try a more Kipling-esque approach to the turtle question.

When the world was new, Oh, Best Beloved, the Turtle was a small, soft creature who played all day with other small, soft turtles on the banks of the great gray greasy Limpopo River all set about with Giant Eucalyptus Trees. He was timid. He was shy. He kept his distance from the great beasts of the jungle. But he was watchful, too, and he learned from what he saw. And so it happened, Oh, Best Beloved, that at the very day, hour, and minute that the Giant Python Rock Snake stretched out the stumpy nose of the Elephant’s Child, the Turtle felt a great fear come upon him. And he ran and rolled himself in the grease of the greasy Limpopo River all set about with Giant Eucalyptus Trees, raced to the most gigantic of the Giant Eucalyptus Trees, embedded his sticky self in the most gigantic of the Giant Eucalyptus Trees seeds, and there remained.

When he felt brave enough to stick his head out, he reported to all the small, soft turtles what he had seen. And thus the world gained not only a Turtle with a Shell, but the very first embedded reporter.

Photo: Luke Norton
This South African sideneck turtle bears a structural resemblance to the fossil of a creature called Eunotosaurus africanus.

Read Full Post »

Evolutionary biologist David Sloan Wilson has just published a book recounting his efforts to apply the principals of his discipline to improving urban life.

The book is called The Neighborhood Project: Using Evolution to Improve My City, One Block at a Time, and it sounds cool.

Mark Oppenheimer writes in the NY Times:

“For years the evolutionary biologist David Sloan Wilson paid little attention to Binghamton, N.Y., where he lived and taught. ‘I hadn’t joined the PTA,’ he writes, ‘attended council meetings, given blood, or served turkey to the homeless on Thanksgiving.’ …

Photographer: Jonathan Cohen

“Five years ago Mr. Wilson, the author of two popular books about Darwin, decided it would be fruitful to apply his training to the (human) animals closer to home. With colleagues at Binghamton University, Mr. Wilson founded the Binghamton Neighborhood Project to use evolutionary theory, along with data collection, to improve the quality of life in his struggling city.”

Although the work is still — evolving — the people he works with make interesting reading as do the experiments.

Oppenheinmer says that the “best chapters describe some of the preliminary work Mr. Wilson’s team has done. For example the Project gave a wide cross section of Binghamton schoolchildren the Development Assessment Profile, a survey that measures sociability, citizenship skills and the conditions that promote such traits. Students rated their agreement with statements like ‘I think it is important to help other people’ and ‘I tell the truth even when it is not easy.’

“The project then figured out where the most trusting, pro-social children lived: which neighborhoods, in other words, seemed to be breeding the most social capital. Using the technology on which Google Earth relies, the project created a krig map — a topographical map representing demographic data — for the city. The valleys showed areas with low social capital, the peaks with high.”

The results have implications for where community-building intiatives might have the most impact. Read the whole review here.

Read Full Post »

%d bloggers like this: