Insects

Insects

All around the world there are entomologists, people who study insects. We should be very proud of these fine folk for without their understanding it would be harder to manage many diseases transmitted by insects, resolve many pathogens, figure out how to assist insects pollinate crops and, most importantly, support insects and their invertebrate cousins maintain soil fertility.

Then there are insect people you might know about. The pest control folk who make sure the fly spray kills the flies and not us.

Sounding a bit posh and, dare we say a little ivory tower, ‘entomologist’ usually refers to the researchers who gather the data and sift through it to find evidence for the good, bad and ugly on the insects that share our spaces. So we can listen to them with some confidence. Not only are they spending their days with ‘bugs’, yuck, they are also the right kind of skeptic using the numbers to find inference.

Lately the number of insects observed by entomologists are in decline. This is not because the entomologists are getting lazy, spending more time watching TV than setting malaise traps or peering down microscopes, but because there are fewer insects around to be studied.

A recent publication confirmed from long-term trapping data in 63 German nature reserves, what many have casually observed in many parts of the world. Insect numbers are going down. And not just by a little bit, they are plummeting.

Hallmann C.A., Sorg M., Jongejans E., Siepel H., Hofland N., Schwan H., Stenmans W., Müller A., Sumser H., Hörren T., Goulson D., de Kroon H. (2017) More than 75% decline over 27 years in total flying insect biomass in protected areas. PLoS ONE, 12(10), eo185809

Three quarters in a generation.

If such a collapse had happened to the Dow Jones the sky would have fallen in. Imagine trying to survive on a quarter of your wages you earned when you started out. Heaven forbid if the defence budget from the 1990s was reduced by all those billions, how scared and vulnerable would we feel?

“Not a problem” the observant reader cries out. “The crawling insects will simply fill the space left by the loss of the flying ones, that’s what you ecology types tell us all the time.”

Perhaps.

Equally a loss in numbers does not necessarily mean a loss of function. Pollination only needs one bee to transfer pollen from stamen to stigma. Fewer mosquitos has to be a good thing and those beetle larvae can’t be doing that much to soil when we have fertilisers.

It is always very easy to play the ostrich. Only they are remarkable and very dumb birds.

When an observation so dramatic and material to so many key ecological processes becomes known we dismiss it at our peril. If we ignore these numbers just because we like the idea of fewer midges at summer evening picnics without looking deeper to find out what is going on, we increase risk to our already precarious food security.

We need to enable our entomologists to find out why the numbers went down and if the decline is going to affect the key ecosystem services we rely on.

Or, of course, we could ignore them and buy more submarines.

Probability

Probability

If a coin is tossed in the air, caught and flipped onto the back of the hand, most people know that there is a 50% chance of calling ‘heads’ and getting it right.

Some will also know that no matter how many times the coin is tossed, and whatever previous sequence of heads and tails has occurred, the probability of calling heads on the next toss and getting it right is still 0.5 or 50%

Alloporus contends that this is about as far as it goes.

Not many of us understand any more of the whys and wherefores of probability than the likelihood of calling head and getting it right, notwithstanding the few who take to the racing tracks. That so many others push coins into slot machines is a bit of a give away. No pun intended.

The next step on the ladder of probabilities requires intuition and so is rather hard to learn.

Suppose I have a group of 100 people.

I know that 50 of them have Irish grandparents and the other half have Scottish grandparents but there is no way of knowing the recent ancestry of an individual without asking them.

I select 10 people at random from the 100 in the room and 8 of them tell me that they have Irish heritage.

I’m expecting it to be 5 but chance can always throw things off a little. Picking just two Scots is unexpected but not impossible.

I select another 10 people at random.

Should my expectation of finding five Irish folk be the same as it was at the start?

Of course, it depends.

If I return my first 10 people to the room to resume their canapes and conversation and I select another 10 people entirely at random with no bias towards those I have already asked, then the answer is yes.

But if I send the first 10 individuals out into the carpark and sample the remaining 90 people at random then the answer is no.

Because by sending the first 10 away (sampling without replacement), I have changed the proportion of Scots in the remaining population of the room. It’s only a small amount but its no longer a 50:50 chance because the proportions of Scots to Irish is now 53:47

Hardly material to any future results. However, if I continue to sample a small population without replacement the proportional change due to my random process of sampling could affect future interpretations. Sample 30 more people and if 20 of them are Scots before we know it its a majority of kilt wearers munching on the salmon pate.

There are any number of thoughts that this simple example should generate from thinking about political poll numbers to whether or not another spin on the pokies is really worth the gamble.

Here is one that may not be at the front of mind.

It’s a truism that most of us do not get probability. My recent ‘ah ha’ moment made me realise that this ‘not getting it’ is pervasive and prevalent even among the technical folk who have been trained in it.

And people don’t get a bit of probability, it’s an all or nothing type understanding. You got the idea behind sampling with replacement not changing the likelihood of sampling a Scot or you didn’t. And it seems that if you didn’t that’s quite OK because, in all probability, you are in the vast majority.

So the thought is this.

How on earth are humans so successful when most of them do not understand chance?

Science and Policy

Science and Policy

In a recent article on why science gets shut out of policy Anthony Bergin from the Australian Strategic Policy Institute contends that

“The extent to which scientific knowledge gets traction in policy will depend partly on the state of science knowledge on the issue, and partly on the degree of controversy surrounding the issue under consideration. It will also depend on the degree of public and political attention the matter gets.”

He goes on to suggest a few reasons for why scientists are not all that good at getting the message across in what is always a consensus and value driven process. Similar to the thinking in Are scientists ready?

In short, scientists too often revert to their necessary scepticism in the face of uncertainty and so come across as weak communicators.

Alternatively Bergin suggests that

“Too often, scientists tend to think they know what is best or what is needed, and then they are disappointed, frustrated or angry when their ideas and hard work are rejected or put on the shelf.”

In other words, they also form and promote values too, just like all the other players in the game. Then their egos get in the way, just like all the other players in the game. Lovely.

I doubt that Bergin is correct in his claim that policymakers do care about scientific evidence if it helps them make decisions. If it helps them make the decision they want to make, perhaps, but that is not quite what he meant. My experience with natural resource management policy is that policymakers understand very little of the science despite their access to considerable in-house and review style expertise. Their political masters understand even less.

Needless to say they all care when evidence helps the spin.

And before everyone whines that policy makers are not in the business of politics, dream on people. It’s 2018, the decade when fake became more influential that fact and public servants found it harder than ever to serve the public when the minister of the day wants her own specific outcome.

So Bergin is right in his tone.

Science into policy is very difficult especially for the scientists.

Scientists do have to front up with confidence, develop communications skills, and learn that their audience has never understood a probability, let alone an inference level.

The use of scenarios makes good sense. It’s the approach that helps AfterBefore Systems to understand options for investment in land management, as does delivering advice in multiple forms. Only my academic experience suggests very few scientists are any good at either of these things. They are hypothesis testers not scenario modellers. They are geared towards output as peer-reviewed papers that create some of the most turgid reading experiences known to man. The poor dears are staring at a very steep cliff.

As with most opinion pieces in this space, the conjecture is easy. In this instance, policy and science are hard to reconcile given the nature of the people involved.

Equally the suggestions are sound. They are easily summarised into “chill out and communicate”.

But wait. The premise here is that inference and evidence will be used should they be understood and available. There is an assumption that human beings are so rational that in the face of evidence they will make the decision pointed to by the evidence.

I doubt it.

Sometimes the evidence is clear. The voluntary inhaling of smoke into your lungs affects your health. Cut down the forest to make arable land and, in time, you will have to fertilize to get a crop. Burn enough fossilised carbon and it will change the composition of the atmosphere. But even blindingly obvious evidence will not always be heeded.

This creates the biggest psychological challenge for the scientist. Trained to find evidence and believe in inference, the scientists is incredulous when obvious evidence is ignored for the short-term expediency of the policy. And this will happen. It has many times already and will continue to happen for as long as there is politics.

The real challenge is making sure that the important evidence gets noticed. Perhaps by being truthful about what happens if it is ignored.


More on this general topic

Are scientists ready?

Post revisited – Leaders not heroes

Time for scepticism