As fate would have it, that weekend I held a similar conversation with a Boy Scout troupe (both the children and the adults) about a dinosaur fossil at the Project Exploration traveling exhibition GIANTS: African Dinosaurs at the Delaware Museum of Natural History.
Is this a bone?
Yes, this is from the back left leg of Jobaria. It is the top part of the leg, called femur or thigh bone.
That's just part of a leg? That dinosaur must have been huge!
Yes, it was about 59 feet long. If that dinosaur were standing in this room right now, it's head would have been through the roof and it's tail out the door. Here, these standing bones next to the fossil are casts of it, and you can compare yourself to the size of the bone to get a better idea.
That really was a huge dinosaur. Were all dinosaurs that big?
Many of them were quite huge, but there have been some small ones discovered as well. The smallest known dinosaur is Compsognathus, which grew to about the size of a turkey.
How do you know that? Did someone write about them?
No, humans didn't exist at the time of the dinosaurs. This particular dinosaur lived about 130 million years ago. We're trying to figure out if any mammals co-existed with dinosaurs, but according to the fossil record, if they did they were only at the beginnings of evolution. These fossils have definitely showed us a lot about dinosaurs; every day that we find a new fossil, we find out new things about them. Sometimes even just studying fossils we've already found will tell us something new about them, or tell us that we were wrong before. It's a lot of guess work.
Wait, what is a fossil record?
Fossils are the preserved remains of life, such as plant or animal material. The materials of this bone were slowly replaced by other minerals, until the bone became stone. A fossil record is the time-line we've built through studying fossils from all over the world of what life existed and what like back then. It's a bit like putting together a jigsaw puzzle without all the pieces.
Are all fossils dinosaur bones?
No, in fact not all bones we find are dinosaur bones. Animals that flew or swim, for example, were not dinosaurs even though they lived on this earth at the same time and looked a lot like dinosaurs. If you look around this room, we also have a fossil of a tree and of a dinosaur foot print. Fossils can be of practically anything, but fossils made from things that were already made of minerals, such as bone and teeth, are much more common. Fossils are still being made today, even.
Is it real? It feels so smooth.
It is real, but it has been coated in varnish to protect it. This is one of the few real fossils that are in this room. Since they are stone, they are often too heavy and fragile to display. Getting to touch a real fossil is a real special occurrence.
How heavy is it?
This fossil weighs about 350lbs.
Wow, so are those other fossils real? (Points to the posed skeleton across the room).
No, those are casts-- if they were real, they would be too heavy to display and the skeleton would likely fall apart.
It's probably more expensive to move the real fossils, too, right?
Right! Not only is it expensive, but sometimes these fossils can't be removed from their country of origin. By making casts, the fossils can remain in the country they were found and be studied by scientists while the casts can travel the world so the rest of us can learn about these amazing creatures.
Why is it so important to learn about these things if they don't exist anymore?
There are a few reasons. First, humans are curious and we have a natural desire to learn new things and solve mysteries. Second, studying fossils may help us to determine for sure how life began, how this planet was created, and maybe even how other planets or how this universe was created. Lastly, by studying what happened to the earth in the past, we can try to understand what is happening to us now. Many fossils have helped us discover more about the process of global warming, and more information may help us learn more about how long this climate change will take, predict the effects, or even figure out how to slow it down.
Slow it down? You mean you can't stop it?
No. The earth is in a perpetual cycle of ice ages, we know that much. Technically we're in an ice age now, as an ice age is any point at which there is permanent ice on the earth. The ice caps are destined to melt one day and the entire earth will be warmer for a time before the next ice age sets in. How long till that happens and how long it will last is what we don't know.
If you can't stop it, what's the point of all these conservationists trying to fight it?
In the past, the cycles of the earth's warming and cooling were caused solely by natural occurrences. Human pollution, however, is effecting these cycles by speeding up the process of climate change. This, coupled with the dramatic increase in extirpated species due to pollution, hunting, habitat infringement, and introduction of other species is destroying ecosystems far faster than nature can counteract. As the problems caused by rapid changes are our fault, it is the responsibility of humans to try to fix them before it is too late not only for other species, but for our own as well.
But why do we need to worry so much? With the technology we have, do we really need nature anymore? Can't we just make it ourselves? What about those biodomes?
Everything we make comes originally from nature- without resources, we cannot do anything. Even if we were to rebuild all of the lost habitat, it will never be the same quality as it was before. There are studies that show that even after 100 years, a rebuilt marshland does not clean the water and provide for the ecosystem as well as the original. It is also a very expensive process to 'make' practically anything, including habitats. Also, technology has not come far enough that we can subsist upon things like 'biodomes' alone. Even if it had, it would be much too expensive and we would not be able to care for the entire human population. Besides, we would be missing out on a great thing-- the natural world.
I guess that's right, I would much rather be able to go outside in the sun and fresh air than be cooped up inside my whole life, even if it looked natural.
Sure you would. Now, can you imagine what it would be like to be a kid a thousand years from now and you don't even know what nature is?
That sounds depressing. That reminds me of when my grandfather used to tell me about how beautiful the woods were around here. When I was a kid I always wished I had woods to play in, there was nothing to do in my neighborhood.
Yea, when I moved to the city I had the same problem. It wasn't safe to go outside, and even if you could there was trash everywhere, and that made you want to be outside even less. I'd take my dog for a walk and end up spending an hour just picking up trash along the way.
Ew, I wish there wasn't so much trash, it's disgusting.
Well, it won't fix the problem everywhere, but you could try reducing trash in your own home and community by practicing composting and recycling. Every little bit helps, and once it catches in in your area, others are encouraged to do it.
That sounds like a lot of work. We don't have much space, either.
It may take up a little more space in your house for the extra bin, but it'll mean you can go longer without taking out the trash, and you can use the compost either for your own plants or gift it to friends and family with gardens. Neither in-home recycling or composting take much work once you learn what goes where.
What do I have to do?
Recycling is easy- just find out what is recycled in your area by looking it up online or calling your local waste authority. Usually it includes things like soda cans, glass, drink bottles, paper, and cardboard. Some places you can recycle more things, like yogurt cups, grocery bags, and snack wrappers. For composting, it's a little bit more involved but not much. You can do it inside or outside so long as it's not freezing: just get a Rubbermaid (any size as long as it's a little tall), drill some drainage holes in the bottom and some air holes on the sides, and fill it with a little dirt. You'll want to put some small worms in there as well, which you can get from a garden or bait shop. Then just put in stuff like leftover fruits, vegetables, tea bags, coffee grinds, eggshells, and paper in there. You don't even have to stir it. In a few days you should have some great compost for gardening.
I don't have a yard to do this in, won't the compost stink up my house?
If there are enough worms, it won't. It may smell a little if you take off the lid and start digging around, but it won't make your house smell if you do an inside compost.
That sounds great, I'll have to think on it some more, but I might try that.
Wonderful! If you want more information, just check out www.howtocompost.org
