If you have a lot of money, you probably have more “of everything”: more clothes, more trips, more books… and, yes: more bugs. That is the surprising conclusion of a work published in the scientific journal Biology Letters .
The researchers started from what is known as the “luxury effect” – the effect of luxury -: in affluent neighborhoods there is usually more vegetation: houses with gardens, parks, open spaces, etc. And it is known that, in fact, the biodiversity in these areas, both at the level of plants and birds, bats and lizards, is much higher than in neighborhoods with lower socioeconomic status.
Because of this, the scientists thought that, inside the houses, the biodiversity of arthropods – a large group of animals that includes insects, spiders, crustaceans , etc. – should be greater in these areas as well, so they launched into collect samples in 50 homes in the state of North Carolina (USA).
In total, 10,000 specimens were obtained from more than 300 different families , and the results confirmed that, indeed, the wealthiest neighborhoods were also richer in vermin. In a curious way, the statistical analyzes revealed that it was not so decisive whether an individual house had more gardens or more vegetation around it: it was enough to be located in an area with a high economic level . That is to say: the biodiversity of arthropods within houses is determined on a neighborhood scale: in those areas there is more vegetation in global terms, and as animals move, it does not matter if your particular house is surrounded by more or fewer plants. : they end up arriving.
The results contradict the general tendency to think that in the poorest areas there will be greater animal wealth in the form of cockroaches, ants, etc. However, we forget that the species that cause pests are a very small percentage compared to the total, especially when it comes to arthropods, the most diverse group of animals that exists.
In any case, the authors acknowledge that this is a very preliminary investigation, since variables such as the diversity of microhabitats within households have not been taken into account , and the sample was somewhat biased towards middle and upper class neighborhoods, with less representation of the lower classes. However, it is a good approach to better understand urban environments and the microfauna that live with us in them.
What is this study for?
Beyond the anecdote, the results of work like this are increasingly important: in a world with a global population that does not stop growing, cities and towns increase day by day, so the living beings with which we share the space are also affected. Human activities have a very strong effect on urban biodiversity , so knowing their patterns and interactions is just as important as studying species from other more “classical” environments such as jungles or forests.
In addition, cities could be a very important ally for conservation . For example: while in agricultural settings, due to the indiscriminate use of pesticides , the biodiversity of pollinators continues to decrease, they could find an unexpected refuge in urban areas.
In fact, some research groups are already looking for the species of plants used in parks and gardens that attract the most pollinators . The use of this type of vegetation cover, together with other initiatives such as insect houses , could help us to alleviate, in part, the damage that we are doing with our aggressive use of the territory.
