Natural instinct and the windscreen phenomenon revisited

Michael - Thursday

This wasn’t meant to be a rant, but I did feel my blood pressure go up when I read the transcript of the president’s interview with Associated Press yesterday. Here’s the piece that upset me (among others, but this is the relevant one):

"Scientists say this [climate change] is nearing a point where this can’t be reversed,” the AP reporters said to Trump.

“No, no,” he replied. “Some say that, and some say differently. I mean, you have scientists on both sides of it. My uncle was a great professor at MIT for many years. Dr. John Trump. And I didn’t talk to him about this particular subject, but I have a natural instinct for science, and I will say that you have scientists on both sides of the picture.”

Okay, so let’s digest this. The president had an uncle who was a scientist. (He was an electrical engineer at MIT, but he died thirty years ago so it’s not too surprising that Trump didn’t discuss climate change with him.) He goes on to claim that he has “a natural instinct for science”. Well, the bad news is that science is not always intuitive. Sometimes it’s counterintuitive. It’s not something that works on the basis of who your relatives are. Certainly, you may have an aptitude for it, but it’s 10% inspiration and 90% perspiration. Come on. General relativity intuitive? Natural instinct for soft quantum hair around black holes?

Of course, you could say that the president is talking about the more everyday stuff that’s actually important to us. Well, let’s go there. If you swing round a corner fast, you can feel the force pulling your car away from the centre of the bend, right? It’s like when you swing a weight around on a piece of string. It wants to fly away – a force is pulling it away from you, right? It even has a name. Centrifugal force. The only thing is, it doesn’t exist. There is no such force. Newton’s laws of motion explain what’s going on. Not intuitive, then. Not what one’s natural instinct would suggest.

And climate change is the same sort of thing. “Natural instinct” might suggest that we are seeing a normal cycle as in the past. That’s Trump’s argument. Actually, that’s not at all what the evidence suggests – in fact, all the natural explanations fail to explain what’s going on. Here’s a really good link to see a graphical summary of that evidence by NASA people who actually put in the 90% of work instead of relying on the 10% of natural instinct. 

And the mathematics is complicated and predicts chaotic behaviour. (I talked about that here.) It does not, for example, imply that we will experience stronger and stronger hurricanes. (Trump pointed out that a much stronger hurricane than e.g. Michael was recorded in the nineteenth century. True, but totally irrelevant.) It implies that we will have less predictable and more extreme weather. Anyone notice any of that recently?

It seems that Trump’s natural instinct has led him to the wrong conclusion, as natural instinct so often does in science.

El Yunque National Forest

So much for the rant. I actually wanted to talk about an update on the windscreen phenomenon. I blogged about that before here. Briefly, it’s the observation that when you drive over some distance these days, you find less bugs squashed on the windscreen than you used to – the suggestion being that we are seeing a die off of insects. There are a variety of explanations for this “bug apocalypse” as someone called it. Among the most obvious are loss of habitat, insecticides, and pollutants.

But a new study has trumped what’s been done in Europe, and it was reported in The Washington Post under the heading: ‘Hyperalarming’ study shows massive insect loss. The new study took place in a pristine rain forest in Puerto Rico – El Yunque. It’s been a protected area since the king of Spain claimed it as his private preserve in the nineteenth century. So it seems that loss of habitat isn’t an issue. At 28,000 acres, and situated on mountain slopes, the area is at least reasonably protected from chemical impact. Also, the use of insecticides in Puerto Rica has declined by 80% since 1969.

The study by a team of biologists was recently published in the Proceedings of the National Academy. In the seventies, they recorded a detailed inventory of the populations of insects, birds and animals in the forest. They returned forty years later (but before last year’s hurricanes) and found an almost 50% decline in the insect populations. Everything was down – butterflies, bees, beetles, grasshoppers, spiders… Some were worse off than others – ground insects measured had decreased 60 fold in biomass.

Ruddy quail dove

There were corresponding declines in the numbers of insect predators – bird and animal – but it was variable. The population of the ruddy quail dove was the same as before. The colourful Puero Rican tody had declined by 90%. The former eats seeds and fruits, the latter eats insects.

So what’s going on? Here are a few clues. The average temperature of the forest has increased by 4 degrees Fahrenheit over the forty years. Insects can’t regulate their body heat, and above a certain point they don’t reproduce. A recent paper in Science on the effects on insects of climate change predicted a decrease in tropical insect populations. An analytic technique applied by the authors of the study to six specific populations produced strong support for a correlation between temperature increase and population decrease in five of the six populations.

Puero Rican tody

And the rain forest itself? So far it looks pretty good. But most plants rely on insects for pollination. If the insects go, the whole system will inevitably collapse. May as well stop worrying about that illegal logging in South America.