CHIMERAS

Let me show you something interesting just before we move away from botany and into Zoology. A few weeks ago, a gardener in Devon, England was harvesting apples from his apple trees and was stunned to discover the apple pictured above. This Golden Delicious apple looks like half of a red apple was attached to half of a green apple. So perfect is the division in color, that some might be tempted to declare it a hoax. But this of course is not the case. The explanation is much more interesting - and bizarre.

This stunning apple is the result of a genetic mutation - a 1,000,000 to 1 occurrence that scientists call a chimera (KI - mera). In Greek mythology, Chimeras were monsters made up of parts from different animals. There are chimeras in the natural world, but they are not made up of parts from different animals. They are made from different combinations of genetic information from the same parents of an animal. Or in this case, a plant.

Chimeras form following the moment of fertilization. Two eggs are fertilized by two sperm, and form two zygotes. Normally, two zygotes will go on to form two distinct individuals. In rare cases though, the two zygotes fuse into a single mega-zygote that goes on to form a single individual containing all of the genetic information from two sperm (or in the case of our apple, two pollen spores) and two eggs. After the resulting zygote's first cell division from one cell to two cells, all future populations of cells and tissue will contain the genetic material and characteristics of the original set of parential genetic material that it has developed from. One side will show characterstics from sperm/egg combo 1, and the other side will result from sperm/egg combo 2. Two cells "split down the middle" so to speak. Then they continue to divide: four, eight, sixteen, thirty two - etc. Up through the creation of an entire organism.

Just to address the question on everyone's mind, no, this does not occur in humans. People are not split down the middle, i.e., brown hair/red hair, light complexion/dark complexion. (Though there are rare instances when odd things do occur. More on that at a later point.....)

Chimeras are indeed rare, but not unheard of. Several years ago while spending a summer in Maine, I visited the "Oceanarium" in Bar Harbor. The prize of that summer's catch was a lobster that had the typical lobster coloring along one side of its body, and a blue color along the other half of its body. The division in coloration ran lengthwise from the head to the tail. This chimera was a star attraction at the Oceanarium, and even made it into the national news. The odds of finding a completely blue lobster are about 2,000,000:1. The odds of finding a chimera in a lobster population is about 1,000,000:1. What were the odds of finding this blue chimera lobster? I'll let you do the math. The probability was small indeed. Even smaller if you figure in the odds of catching it. But even unimaginably small probabilities do make themselves seen when populations are large enough. And in a world that is connected electronically, these discoveries become known and shared instantaineously between continents.

Chimeras serve no adaptive purpose. They are simply the result of random genetic mutations and combinations. Sometimes, 1,000,000 to 1 odds become an individual's 100%.

The Wild Things

I’ve been thinking a lot about our trip to NYC since getting back. It really was a lot of fun; very enjoyable, and so many things to think about and reflect on. There were many highlights for me; I certainly won’t forget the “wows” when everyone got their initial glimpse of the Apatosaurus and T. rex skeletons. (Similar responses were noted at the Hall Of Oceans, for the model of the Blue Whale) Certainly the rhinosaurus, and gorillas at the zoo are always thrilling. And I'll always have many fond amusing memories just from our travels together. Blue Jay carrying his dinner proudly over to my table to share that he got his New York steak, and Caleigh texting Maggie – one seat away in the movie theater for example. Some moments gave me new insights into students. Lui looking at the Indian brass and artwork reflecting on her semester in Ledoc and saying how it was “weird…now I understand what this stuff means” and Caleigh, applying her knowledge of equine care to the giraffes; observing and hypothesizing that they might need medical care. Ben, whose interest in everything herpetological was exceeded only by his interest in anything edible. And rest assured I will never look at Capt. James T. Kirk in quite the same way again.

I also appreciated how many of you commented on your enjoyment and appreciation of the dioramas. It was Chris’s succinct comment about the dioramas (he thought they were “wicked awesome”) that really set me off on a great deal of thought and reflection about them. I agree with Chris, they were “wicked awesome”. But I haven’t always felt that way.

I first saw the dioramas at the American Museum of Natural History when I was a kid of maybe six or eight. Growing up in Brooklyn, I went on my own school field trips to the museum, and later as an adult I brought my own kids to the museum when they were about that same age. Throughout that period of time, I must admit that I never really cared much for the dioramas. I thought of them as being fairly dull and lifeless. Antique relics of a bygone era of museum science. (or art). The dioramas were designed to make exotic, foreign life forms accessible to the masses. Keep in mind that most people had never seen live giraffes, lions, or elephants until the 19th century. Looking at the dioramas as a kid (and as a young adult) I saw an antique exhibition of inanimate, rather than living, objects. Mere stuffed relics from a bygone era.

Returning to the museum with you, allowed me to re-visit and see these dioramas with new eyes (well, older ones anyhow). I now appreciated the tremendous artistic detail that went into each the recreation of each animal’s habitat in each diorama. I was stunned at how each diorama was designed to capture a dramatic moment in the narrative of the animals’ lives. Think about the Ostrich, its wings outstretched, protecting its young from predators. Or the Cheetahs on the prowl through the forest. The two male Alaska Moose, engaged in combat thrusting his rack into his competitor’s thorax. Mountain Gorillas, with the alpha male proudly beating his chest, re-asserting his dominance over his band, or troop. And the gentle Nile River ecosystem, with its animal communities all gathering to sip the precious liquid of life.

Looking at these dioramas now, I was re-awakened to their beauty, but I also experienced a new a sense of sadness. In a span fifty years, many of these creatures have become endangered. It now seems quite possible – if not probable – that some may become critically endangered, to the point of possible extinction. Many seem to be on the verge of disappearing from the earth. The Hall Of Oceans boasted in its diorama that the polar bear is the “top predator of this icy world”. But its world of ice is melting at an alarming rate – a rate far greater than recent predictions. And polar bears – while still plentiful – are facing extraordinarily adverse conditions, and may become extinct by the end of this century. Polar bears may live on frozen land, but they are land creatures - not sea creatures. Their habitat is melting away beneath them. Adrift on glaciers, polar bears struggle to swim increasingly long distances between arctic land masses. If a top predator disappears – even one that lords over an icy world - its surrounding ecosystem collapses along with it.

Perhaps one day one or more of you will return to the museum with your own students, or your own children. I suppose you will reminisce about our trip to New York way back in the year 2009. No doubt you’ll laugh at the quaint gasoline powered vehicles in which we drove down to the city, the flat screen upon which a “film” called Where The Wild Things Are was projected, and perhaps you'll even laugh at those little boxes called iPods that used to play your music. (How much longer before we all have our personalized playlists etched on a chip in our heads?)

Your students or children will no doubt also express amazement at the Apatosaurus and T. Rex skeletons. And as you make your way down from the fourth floor to the second and first floors that house the dioramas you will no doubt stop, and re-experience the wonder. But what will you say when the child you’re with asks you if you REALLY got to see a live gorilla or a giant white polar bear? How will you answer their questions about why they all died – or how people could have allowed them to disappear? Looking at all the technology that will no doubt surround you in the 21st century, how will you respond when they ask, “Why didn’t people do more to save them”?

What will go through your mind, 40 years from now, as you re-visit and gaze upon the same dioramas at the American Museum of Natural History. What will it be like to be an adult, knowing that your childhood was the last during which kids grew up with the knowledge that somewhere in the world, in a place far, far away there existed a wondrous world of ice and mysterious forested jungle - places Where The Wild Things Were?

What is this?

Hello Zooboters! Sorry - I missed you guys on Friday, and I really don't know if I'll make it in tomorrow either as I'm still running a low fever from this nasty flu. (Don't think its "swine-y" though...). So this response will be wrapped up into my "sub-plan" for the day.

So I'd like you to response to this picture with your best guess of what this image actually is.

Once you decide what it is, I would like you to write a short essay about this, uh, whatever-it-is. Do not write this on the blog, just identify this thing in your response. On a SEPARATE SHEET OF PAPER please write what you imagine this "things" life cycle to be. Please discuss its birth, habitat, predator prey relationships, young life, reproduction, family and social interactions, and death.

I'll collect these stories - best one wins, er, something.

Modern Snake With Legs, and Primitive Snake With Feathers

This is just to post the picture - read and respond to the NEXT post below on Dinosaurs and Birds!

Birds DID evolve from Dinosaurs!

Scientists have long debated the evolutionary ancestry of birds. During the past decade, evidence has emerged that birds evolved from dinosaurs. This past month, scientists in China discovered an amazingly well preserved fossil that seems to finally put the question to rest.

Xing Xu of the Chinese Academy of Science in Beijing has discovered the remains of a "four-winged" dinosaur that seems to confirm that birds owe their ancestry to dinosaurs living millions of years ago. The "dino-bird", called Anchiornis huxleyi.
Until now, incomplete fossils suggested that A. huxleyi was a fully transitioned primitive bird. The fossil is clearly transitional and dinosaur-like - providing almost indisputable evidence that proves birds descended from dinosaurs.

Xu and his team discovered a dinosaur with long feathers covering its arms, tail as well as its feet. This is an arrangement of a "four-winged" dinosaur does not prove that the creature could fly. It also had long lower legs that suggest it was a good runner. But the well-preserved fossilized feathers do show a "transitional species" that illustrates how bird-like dinosaurs developed features enabling them to fly.

The astounding fossil comes from in Daxishan, in Jianchang county in northeastern China. It was found in rock dated to the early part of the Late Jurassic period, about 160 million years ago. This date means that A. huxleyi is not a true bird, but rather a a late member of the Troodontidae, a category of dinosaurs closely related to birds, Xu said.

Xu concludes that his discovery proves once and for all that dinosaurs and bird-like creatures did exist at the same time, and that the family of modern avians descended and evolved from reptilian ancestry.

As for the reptiles themselves, I only remind you of the other discovery I mentioned in passing this week - a rare snake with fully developed legs. Discovered - again - in China.

What does this modern mutant suggest to you?