The California Academy of Sciences, located in San Francisco's Golden Gate Park, is one of the finest natural history museums in the country. If you get the opportunity to go there, I urge you to do so. Unfortunately, not everything in the museum deserves to be called "science."
The following statement is one of the informational posters that's part of an area called "Climate Change." It is like other such claims I've seen numerous times in similar venues over the past several years. The poster is titled, "Rushing to Extinction," and has been part of the exhibit for at least two years that I know of.
Today, we are living through the sixth mass extinction of life in Earth's history. This is due in part to climate change triggered by the carbon dioxide we pump into the air as we burn fossil fuels for energy. The resulting greenhouse gases are altering the biosphere, which is causing the loss of plants and animals around the world. If we don't change our actions, we could condemn half of all species to extinction in a hundred years. That adds up to almost a million types of plants and animals that could disappear.
I urge you to read the statement again and consider what it says. Although the statement is extreme and sensationalistic, it is not unusual. It is typical of the conventional wisdom. It is ironic that it is found in what is called the California Academy of Sciences. It is reckless fear-mongering propaganda, not science. It cannot be substantiated and is a total distortion of reality.
For example, it is simply not true that "Today, we are living through the sixth mass extinction of life." About 770 plants and animals have been identified as having gone extinct in the past 800 years. That's about one per year. We are discovering far more species we did not know about than identifying extinctions.
The poster implies there are a total of two million species now existing. Biologists don't actually know how many species there are. Educated guesses range between five million and fifty million.
Even if the total number of species is only two million, it means that if half go extinct in the next hundred years, the rate of extinction will have to increase from one each year to 10,000 each year. What's the probability of such a massive change? How, specifically, is that going to happen?
Previous mass extinctions were the result of asteroids or ice ages. Have we had one of these lately that I didn't hear about?
Is the statement defensible? It's a statement made in a certain context, the Academy of Sciences. Apparently it's an assertion that is supposed to be accepted based on authority. If you're going to make such a cataclysmic prediction, shouldn't you provide a little documentation and support? Is it supposes to be self-evident?
To this point "climate change" has not increased the rate of extinction. We definitely are not currently "living through the sixth mass extinction of life." To say we will in the future is speculation, about which there is much disagreement, to put it mildly. There is definitely no "consensus."
The poster is worded as if what it says is beyond dispute. The statements are not qualified in any way. I assume the designers of the exhibit intend for it to be taken seriously.
"If we don't change our actions, we could condemn half of all species of life on earth today to extinction in a hundred years." You can get away with about any outlandish prediction you want to make if you hide behind the word "could." In the context of basic scientific protocol, any such statement should be presented in terms of probabilities as well as a discussion of the specific preconditions to such an event.
Judging from the numerous groups of children I see when I go there, the Academy of Sciences is possibly the most popular destination for Bay Area schools' field trips. The statement, which is truly frightening if you believe it, is seen by hundreds of school children almost every day. What kind of impact do you think such statements have on young, impressionable minds? It verges on emotional child abuse. The Academy staff should be ashamed of themselves, but I doubt they are.
Environmentalists are so fanatical about their Armageddon beliefs that they think terrifying school children is justified. Do these people ever think about the implications of what they say? Do they care?
The purpose of the "Rushing to Extinction" poster and similar statements is to deliberately frighten whoever reads it. Environmentalists apparently get a perverse thrill from scaring people and making them feel guilty for being members of the human race. The California Academy of Sciences is allowing itself to be used as a venue for manipulative propaganda.
The natural world is fascinating and magical. The best way to illustrate that is to stick with the facts. It's too bad natural history museums don't do so.