Hundreds of parasites are also threatened with extinction with primates and that can have major consequences

Parasites: they are not so huggable, but they are very important and in danger.

The future doesn’t look bright for many of the primates closely related to us. About half of the roughly 500 species of primates that can still be found on Earth today are in danger of extinction. And we can be quite concerned about that. Rarely, however, is there any mention of the countless parasites that these primates carry with them and that – along with their hosts – are in danger of extinction. “If all endangered primates really do go extinct, they won’t be the only species that disappear,” said researcher James Herrera. “Twice as many parasites can also be lost.”

Worrying

And while those parasites may not initially evoke feelings as warm as the endangered primates, it’s worrisome. “That’s a part of biodiversity that would die out without us really noticing. We know so little about what the parasites do in the body that we don’t really know what we’re getting rid of.”

The research

In an effort to get a little more grip on what we risk losing at the parasitic level, Herrera and colleagues have developed a model. This model describes the interactions between 213 primate species – from monkeys to lemurs and galagos – and 763 parasites – such as worms and mites. They then looked at what happened when certain primate species went extinct. The investigation paints a rather grim picture.

The consequences of extinction

Once a primate species becomes extinct, parasites lose one host. That can be fatal for a parasite that can only survive in this primate. But even less picky parasites are not sure about their lives, the researchers emphasize. Because at the moment about half of all primate species are threatened with extinction. And when several primate species disappear from the ecosystem, parasites that previously had several hosts to choose from can also lose out.

250 parasites

And the model makes it painfully clear that we are in danger of losing so many parasites. Of the 213 primate species that the researchers included in the model, 108 are in danger of extinction. If they all disappear, an estimated 176 parasites will no longer have a host and will therefore be doomed to extinction.

Madagascar

The researchers are particularly concerned about primates that live in isolated areas. For example, they think of Madagascar, where no less than 95 percent of the lemurs species are in danger of disappearing due to habitat damage, illegal hunting and animal trade. More than 60 percent of the parasites that inhabit these lemurs depend on one species for their survival. And that makes them particularly vulnerable.

The importance of parasites

Perhaps the loss of these parasites does little for you. After all, we humans are mainly used to fighting parasites tooth and nail; we deworm our pets and delouise the children eagerly. But it’s very important to remember that parasites don’t always cause noticeable symptoms or illness, Herrera points out. In fact, some parasites are good for us. For example, there are indications that parasitic worms that live in the gut can fight infections and fight autoimmune diseases. However, for many of the parasites that live in primates, we don’t know exactly what they do in their host and what role they play or the primate-parasite interaction in the larger ecosystem. In fact, we do not know a large part of the parasites at all. For example, a recent study suggested that 85 to 95 percent of the parasitic worms that inhabit animals have not even been discovered!

Malaria

Finally, the disappearance of primate species may also cause their less finicky parasites to jump in desperation to hosts that are still abundant. Consider, for example, the primate-like human being. Based on their analysis, the researchers are unable to estimate how many parasites can make the switch to another species. But it is certain that it can happen. It is also not inconceivable that such a parasite can cause a lot of misery. After all, there are several diseases that now occur among humans, but which we know originated in primates. Consider, for example, malaria caused by a parasite.

The research is therefore a plea for saving primates and the species they harbor. However, it is also of great importance that we clarify which parasites live in primates, what their functions are, to what extent they are also threatened with extinction and how big the chance is that they jump to other species. “Parasites are an important part of ecosystems and understanding these ecological networks is crucial if we want to preserve ecosystem functionality,” the researchers conclude.