Science Friday: What separates us from the chimps?

karate chimp

What separates us from the chimps? For starters, that we are formulating such a question (big brains), voicing the question (speech), and investigating its answer using computers (tool manipulation).

99% of our DNA is identical to chimp DNA (in sequence, let’s not forget epigenetics and post-transcriptional control, the up-and-coming underdogs of biology). Your first thoughts might be that key genetic differences underly appearance (e.g. standing upright) and memory (e.g. remembering an entire spoken language). But researchers in several groups across the U.S. found much more.

Genes undergoing positive selection change more rapidly than those undergoing random (neither-beneficial nor harmful) mutations. So by comparing genomes across several species, scientists identified human genes highly divergent from chimp. The functions of these genes are not fully understood, as always is the case with science.

List of key genes identified:

1. Gene that is turned on during development, the product of which (called a protein) helps to sculpt the thumb from the rest of the hand. This gene helps to explain humans’ increased dexterity over chimps, and thereby the construction of more complex tools and the manipulation of the external world. (Can a chimp tie a shoe-lace? Doubtful.)

2. Two genes in diet: one that breaks down lactose and one that aids with starch digestion in the mouth. A flexible diet means a flexible lifestyle. Nature favors the flexible.

3. Gene involved in the production of speech, on the anatomical level. As an analogy, the violin can’t make music without strings (its anatomy), we can’t say words without our speech anatomy (certain bones and things, I won’t go into details). This one interests me particularly. When I think of language, I think of advanced mental faculty. I think of writing poetry that elevates the soul and composing song that crushes our proverbial fragile frames, not the height of the hyoid bone. Fascinates me to bits.

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Science Friday: Jellyfish

“Sea Jellies”: all photos opensource

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Chrysaora quinquecirrha

Jellyfish have no specialized circulatory, digestive, or central nervous systems, yet they are one of the most successful creatures on Earth as measured by biomass. Some are cannibals; some have fatal stings; some are immortal; some glow in the dark; some are bigger than blue whales; some have gender (male or female); they are all awesome to look at.

Some are larger than blue whales.

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Cyanea capillata: Called the Lion’s Mane Jellyfish

I always thought the blue whale was the largest ocean-dweller but not so! (It is the largest mammal.) Lion’s Mane Jellyfish that have washed up on beaches are around 120 feet long, the length of three school buses. This jellyfish lives in the cold, boreal waters of the Arctic, which is pretty cool ;)

Some are immortal.

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Life cycle of Turritopsis nutricula

The life cycle of a normal non-immortal jellyfish is complicated, but basically they exist as polyps, which reproduce asexually by budding, and then as medussa, tiny jellyfish that swim away from the polyp, and then as the larger bell-shaped sexually mature form. Turritopsis nutricula are able to revert to the polyp stage after becoming sexually mature, through a process known as transdifferentiation. Transdifferentiation is rare in biology; it’s when a differentiated stem cell takes a fate outside its established path. Basically it would be like a hair cell becoming a red blood cell, instead of a stem cell becoming a red blood cell. Transdifferentiation sounds risky and biologically pricey to me, but perhaps in evolution, great risks reap great rewards: Immortality!

 

In groups they are called blooms, swarms, or smacks.

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A smack of jellyfish.

They are smacking into each other so to speak. This shot was taken in a aquarium, which are often backlit to highlight the jellyfishs’ loveliness.

 

Some glow in the dark.

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Jellyfish proteins in a petri dish: Green Florescent Protein (GFP) etc.

GFP was originally isolated from Aequorea victoria and is now a common biological tool that researchers use to study cell shape and protein localization and function. The GFP gene has been modified to emit different color light, including red (RFP), yellow (YFP), cyan (CFP), magenta (MFP), and more — see beautiful beach scene above! In 2008 GFP won the Nobel Prize.

 

They are all awesome to look at.

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Mediterranean Jellyfish

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Palau Jellyfish

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Flower Hat Jellyfish

 

Mr. and Mrs. Lighthouse *December 25*

Science Friday: Major/Minor Evolution

One can speak about music in endless technical detail, from what separates a major from a minor key, and how to resolve from dominant to tonic. But what about the purpose of music not only in our daily lives but also in the view of human evolution?

Fillippino Lippi

Music is as old as rain -- "Allegory of Music" by Fillippino Lippi (c 1480)

My thoughts on the prominence of music in human lives~

1) On making music: The earliest music no doubt centered around song. The human voice is an expressive and convenient instrument. It’s possible that singing and the earliest arrival of language supplemented each other. Speech requires certain muscles and skills that one practices and hones while singing. On top of that, communities with a rich oral history not only pass down fables through speech and song, but also wisdom and learning. Therefore communities that used music to convey cautionary tales or how to hunt at night or raise a baby might survive better than less communicative tribes.

2) On creativity: A similar thought to above. More creative communities flourished. Creative communities were singers. Our successful ancestors were singers. We are now singers.

3) On group love: Humans are social like nobody’s business. Social bonds strengthen communities and help the individuals within the communities. Playing music together is a bonding ritual. So music elevates love and therefore commitment and even personal sacrifice for the good of the group.

4) On getting down n’ dirty: If you can’t mate, you can’t procreate. You can’t even proginate. (See how I just made a little song there?) Music and dancing are like mac and cheese. Dancing and mating are like also like mac and cheese. Follow my logic? Another note on mating, male birds with the most complex birdsong, lots of trills and embellishments and ornamentation, get more lady birds to make chicks with.

There’s a recently published article here that I haven’t gotten to read yet on music and human evolution.

Humans are pretty complicated, no? I like that about humans, but I also like ants. Ants operate so simply but so succesfully. I wonder if they have little ant symphonies?

Mr. and Mrs. Lighthouse *December 16*

Science Friday: Who will be the next Albert Einstein?

 

(einstein_tongue)
(rf_dream)
I’m a big fan of the little ones. On Wednesday I judged a science fair for gradeschoolers, adorable micro-scientists with a sense of play to rival Einstein himself. Here are some tidbits from my interviews. Most students were impressive, some were funny, many were both.

 

1) The scene: A 3rd grade girl with braces. Incredibly shy, no eye-contact. She wants to be in an earthquake but is too scared. So for her project she decided to sit in a chair and have her parents shake it. I asked her what she measured because science is all about numbers. Turns out she measured the strength of the “earthquake” by the amount of Lucky Charms cereal that spilled out of the bowl on her lap. Tell me this isn’t creative, I dare you.

2) The scene: A 3rd grade girl with lavender nail polish and a project on household disinfectants and eliminating germs. Her hypothesis: “The Pine-Sol will kill the lunchmeat!” (Take a second to form an image with this one.) And what made her misunderstanding so charming was that she really owned her hypothesis and loved her project.

3) The scene: A 4th grade boy waiting with his friends to be called to his interview. He had his hood up, was punching his buddy in the shoulder, and whistled Chopin’s death march when I called his name. A real bad boy. Now fast forward thirty seconds. We are standing alone in front of his poster, just the two of us.

Nicole: What question are you trying to answer with your project?

“Bad Boy” (jumping up and down): “I really love computers! I wanted to find a way to increase my wireless signal using different shapes wrapped in aluminum!” and on and on.

Enchanting, enchanting, enchanting — if only I could bottle his enthusiasm and give it to researchers before conference presentations.

4) The scene: A 2nd grade boy with a project entitled “DISCOVERING DENSITY”

His data consisted of crayon drawings of submarines surrounded by fish (remember how you used to draw fish as a kid, with one line, always orange) and cruise ships with smoke coming out of their stacks. I think all doodles should be considered data – papers would be more fun to read.

Here for entertainment value, I’ve included funny, cute anecdotes.  But these kids really blew me away with their smarts. Judging their projects was an honor, and even though not all of them will be the next Albert Einstein, I bet lots of them bring joy or truth into the world in their own ways.

 

 

Science Friday: I can make your brain glow

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I love brains. They are the nimblest, sexiest, most adorable organs imaginable.  They are worlds all their own.  They have worlds within worlds. They have more connections than atoms in the universe. They look like the universe. Out of randomness arises idiosyncratic complexity.

Posted here are microscope images I took of mouse brain cells in vitro. (In vivo brains look different in 3D.) The long, spiny outgrowths allow brain cells to chat using chemicals and electricity, sort of like telephone cables. The brain cells glow because I injected DNA that makes certain cell components emit light. By looking at how cells glow depending on what DNA (genes) we inject, scientists can learn about not only gene function, but also about cell shape, cell-to-cell communication, cell behavior, and internal cell organization. Brains aren’t only useful – they are beautiful.

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No mice were harmed in the making of this blog.