adaptation

Showing 7 posts tagged adaptation

The question “Who was the first human?” was a very popular one in our house just last year, but the evolution videos we had in the archives – even the awesome Five Fingers of Evolution TED Ed video – didn’t answer it directly enough for my kids. This visual-filled video timeline from Joe Hanson of It’s Okay to Be Smart does: There was no first human.

You can never pinpoint the exact moment that a species came to be, because it never did. Just like how you used to be a baby and now you’re older, but there was no single day when you went to bed young and woke up old…

There was no first human. It sounds like a paradox, it sounds like it breaks the whole theory of evolution, but it’s really a key to truly understanding how evolution works. 

Also, your grandparents (a hundred eight-five million generations removed) were fish!

In the archives, more videos about evolution, Neil deGrasse Tyson explains evolution, and a related must-watch video about our human history: Carl Sagan’s Cosmic Calendar from the original Cosmos.

From jtotheizzoe.

This incredible animation by Flora Lichtman and Sharon Shattuck chronicles the story of British naturalist, anthropologist, biologist, geographer, and intrepid adventurer Alfred Russel Wallace, who was also Charles Darwin's lesser-known partner on the joint presentation On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection. From Smithsonian Mag: 

It was during fits of malaria that Wallace started to come up with the idea of natural selection. He sent his manuscript to Darwin, who puts together a set of notes to be presented alongside Wallace’s. When the Linnean Society of London hears the case for natural selection in 1858, Wallace and Darwin share the credit.

So what happened? Why do we remember Darwin and not Wallace? Well, for one, when Darwin published On the Origin of Species, he barely mentions Wallace at all. And Wallace doesn’t complain. In fact, he loves the book. And with that, he fades away.

Though we doubt the story was quite that simple. Read more about the differences of their ideas, see more of Wallace’s Collection (like these) at London’s Natural History Museum, and check out another of his contributions: the Wallace Line.

Related watching: TED Ed’s Five Fingers of Evolution and How Mendel’s pea plants helped us understand genetics, and previously from Lichtman and Shattuck, a favorite: Whale Fall (After Life of a Whale).

via sagan sense.

In this extraordinary adaptation strategy, Thailand’s Moken sea gypsies can see twice as clearly underwater by controlling the size of their pupils. What was generally considered an automatic reflex for the rest of us is now thought to be something that any child under 5 could learn how to do.

From a study called Superior Underwater Vision in a Human Population of Sea Gypsies by Dr. Anna Gislén:

The Moken may learn to do this due to their extensive use of their eyes in water, where accommodation and concurrent pupil constriction is necessary for them to see the items they gather for food. It should then be possible for all humans to learn to see better underwater. But because sea gypsies have lived by and off the sea for thousands of years, evolution may also have favored those who had intrinsically better underwater accommodative powers. The ability to see well underwater could have become a genetic trait. Another possible explanation is that accommodation underwater is a side effect of the diving response; the parasympathetic nerves that control this reflex also control pupil constriction.

Read more at National Geographic.

In the archives: more swimming and these extreme eye closeups.

From the chopping of ice chunks high on the Mount Chimborazo to hearing firsthand about this family’s traditions, The Last Ice Merchant (El Último Hielero) is an engaging documentary about a man’s dedication to hard work and a way of life that has changed. (And the subtitles are at a good pace for reading out loud to younger kiddos.)

Twice a week for over half a century, Baltazar Ushca has hiked up the slopes of Mount Chimborazo, the tallest mountain in Ecuador, to harvest glacial ice that covers the highest altitudes of this dormant volcano. In the past, up to forty ice merchants made the journey up the mountain to mine the ice; today, however, Baltazar works alone. Even his brothers, Gregorio and Juan, both raised as ice merchants, have retired from the mountain to find more steady work.

Excellent storytelling by director Sandy Patch. The kid(s) should definitely see this. 

There are more documentary clips and more ice in the archives.