Family Holloway

I was recently asked by a NZ primary school student to help explain evolution for a 5 minute presentation. Naturally I told them that I’m not qualified but I gave them some pointers to youtube videos about it, and I provided the following speech. I had to make some generalizations but I tried to be accurate and here’s what I sent her:

You might have heard people say you look like your parents.. perhaps you have your mother’s eyes, or father’s ears. When you were in your mother’s womb you grew your eyes and ears from a recipe called DNA: Deoxyribonucleic acid, which tells bodies how to grow. DNA is a recipe for life, and all living things on earth use it to grow and reproduce. Trees have DNA and so do all animals. Human children are all the result of about 50% of our parents DNA with 100 to 200 mutations, which is why we look a bit like each of our parents. Because of your parents DNA and those 100-200 mutations your DNA is unique (unless you’ve got a twin).  Little bits of DNA is in all parts of our bodies.. in our blood, our muscles, and our hair. If a crime scene had DNA that was like yours but not quite the same then it would mean that the DNA was from someone in your family.

A poodle is a weird animal that didn’t exist 500 years ago. Dogs are domesticated wolves, and since people began breeding wolves we’ve been able to breed them into poodles, chihuahuas, and other hairy and hairless dogs. Someone trying to make a friendly dog would just breed friendly dogs together to get friendly dog DNA. Someone trying to make a small dog would breed the smallest dogs together to get small dog DNA. People breed dogs, horses, birds, and all kinds of plants. People breed all kinds of life on earth, and what they’re controlling is DNA. A scientist named Charles Darwin wondered if people could make such a massive change to dogs by breeding them then could nature do it too? In wild forests would weak animals get food, or would the strong get food? If there was a strong animal would it have more children? What Darwin discovered was that nature had a natural ability to breed… to naturally allow the smartest and strongest to survive. About 150 years ago he wrote a book that explained this and it was called “On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life”

What Darwin discovered is that just like dog breeders being able to encourage the growth of small dogs, nature had been breeding all life on earth for a long time. Dogs can be bred to the size of chihuahuas in a few hundred years, but nature had been doing it for millions of years. About 200,000 years ago there weren’t any people, but there were ancestors of apes. The weakest and dumbest of these ancient apes didn’t have as many children as the strongest and smartest, and due to those mutations (that we talked about earlier) these ancient apes split into distinct populations. One of these populations eventually became humans. Before apes were fish that breathed air called lung fish. and before that were fish in the water. Life keeps changing shape and adapting. So all life on earth is related in a big family tree that looks like this

This is called Evolution, which is a fact and a theory about how every life form is related and how different species of plants and animals arose. Although some people don’t believe in Evolution they have never been able to prove it wrong and infact Evolution has mountains worth of evidence.

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