The teacher said it was too big. Too big, smig my 12 year old mind thought. What does she know? I was going to win and I had the winning topic. I loved animals.
I did the project. I didn't win. I remember putting my project out in all it's glory. It was toward the end of the row on the gym floor. This kid who I did not think was too bright had a huge project. His mom was working hard as he watched. He won, I lost.
By the time I got to ninth grade, I managed a third place. I made models of isotopes just like the World Book Encyclopedia suggested in it's science fair project presentation. The teacher told me I had a crummy project. It was a model.
The project was not that great. The ninth grade teacher was honest. Science fair projects using experimentation are preferred. The seventh grade teacher fades from my memory. If it wasn't my seventh grade science teacher. Perhaps it was a project in elementary.
Anyway, for the A to Z topic. It is perfect. And I plan to discuss one item about zoology and that is symbiosis since that has a Z sound.
I've always liked symbiosis in that two different species work together. However, mutualism where both benefit was my real preference.
Pine trees have a fungus in their roots called mycorhiza which help the pine tree absorb nutrients and of course the fungi makes food and reproduces with the pine tree's help. This is a case of mutualism.
Parasitism is also a symbiotic relationship. A successful parasite does not kill it's host. So HIV is not a successful parasite. Interesting enough viruses are thought to arise from the organism it infects. Viruses are somewhere between the living and non-living world. They cannot become active and reproduce without a host. Other than that, they are just scrap DNA in the dirt or where ever they are.
A friend of mine whose family were ethnic Germans who spent World War II in the Phillipines tells about having worms as a child. She had an uncle who had peppermints that were actually a laxative. He told her she could eat some. Being a child, she ate the whole bottle. As a result, she had diarhea and expelled the most worms. After that, she began to gain weight and wasn't so skinny. The worms were a successful parasite in that they did not kill her. Their presence weakened her.
Commensalism is where one organism benefits and the other is unaffected. Small fish swimming with sharks to eat scraps of food that escapes the sharks mouth is an example.
Domesticated dogs are put with commensalisms but it is actually a symbiotic relationship. The beginning dog was a wolf-dog that was neither a wolf or a modern dog. It was in transition. The fact that the dog benefited from living with humans is evidenced in there was a decline in the brain. When animals are benefited by another species, that brain function not used tends to be loss as the two species evolve together.
How we know that dogs benefited humans too is that humans also had a brain decline of about ten percent compared to the dog's twenty percent. Dogs got more out of the relationship.
The wolf-dog defended territory, brought home meat, helped with hunting in exchange for sitting around the campfire and being fed by the humans. I have read but have forgotten the source that without dogs, man would have probably died out. Then we would have had a real planet of the apes.
People may think the dog today does nothing. But, my dogs do alert me to strangers. The terriers efficiently hunt mice which can be a problem. And their emotional support is tremendous. I have a sister with mental illness and the dogs in our home reduced her need of medication. She still needs medication. It is a chronic disease. But the mood elevation helps her cope.
|Louise hopping to flush out mice.|
|What do you mean I'm not supposed to be on the bed?|