Lorenzo Perissinotto, Professor of Marine Biology, Zoology and Entomology at Rhodes University, South Africa, in the field discussing species, in particular invertebrates, and their environment.
The problem is that the layman generally refers to animals, meaning they are big and hairy, at least the vertebrates, and in the great scheme of things they actually constitute only 5% of the total biodiversity. There are 47 000 species of vertebrates in total, worldwide, and there are for instance, just of insects, we know currently of 350 000 species. So that tells you the sheer difference between in the world of invertebrates. There are over 1 million in invertebrates, versus 47 000 vertebrates.
We estimate that we could be anything in the total number of organisms, we could have anything between 10 and 100 million species. We are describing 10 000 on land and shallow waters including the coastal ocean but we have hardly explored the abysmal part of the ocean, where we expect to find lots of new species and at the moment we have 1.8 million described, between animal, plants, fungi and bacteria.
With insecticides, you also run the risk of unintended consequences of killing insects that are not the target. If that happens and you drive some species into extinction, you have cascading effects, with other species providing food to another species, or was controlling another pest, so that’s the problem. Before you target a species, you need to know exactly what the predator is, or what the prey of that species is. What it consumes and what consumes it. So that you don’t create a negative cascading effect on the ecosystem, because by eliminating one species you could affect more than the entire food web.
We are only concerned with one species and that’s us. Homosapiens. We pretend that we care about the rest, but the vast majority of the 7 billion people, are all too concerned about feeding themselves, getting a good standard of living and making more of them.