for insects as such but rather a fear of the
knock-on effects of insect loss on more visible
and “popular” organisms, such as the birds and
mammals that eat them, or the trees and shrubs
that they pollinate. However, a strong decline
of insects—even just beetles—would have
far- reaching implications that would impact
the overall function of global ecosystems.
As well as providing food for many other
invertebrates and vertebrates, and playing little
recognized but major roles as pollinators and
predators, beetles and their larvae have an
essential role to play in returning nutrients to the
soil and making them available again for new
plant growth. European settlers in Australia
received just a small taste of what could happen
if these systems are unbalanced, when they
introduced sheep and cattle to Australia without
the suitable dung beetles to clear up the waste.
What was almost an ecological disaster was
averted by the selective introduction of European
and African dung beetles, but if this had not
been done, or had been unsuccessful, the entire
Australian sheep and cattle industry might
ultimately have become unsustainable. This
imbalance could be fixed only because it was on
a continental and not a global scale, but if dung
beetles were to disappear globally, so that more
could not be brought in from somewhere else,
humanity could be faced with an agricultural
crisis. This scenario may not be as distant or
unrealistic as it sounds. For example, the
widespread use of ivermectin wormers to kill
intestinal worms in livestock may be destructive to
dung beetle populations because these pesticides
are nonselective and remain active in the dung
after it has passed through the animal, killing
many of the insects that would otherwise break
down the dung.
The famous US entomologist E.O. Wilson
(1929–2021) described insects as “the little things
that run the world,” and this quotation is very apt.
When we look at a tropical rainforest, we see
trees and flowers, and we hope to see, perhaps,
orangutans, tapirs, or jaguars. But what is much
more fundamental is the vast, underappreciated,
and in many cases still undescribed diversity of
beetles that, in their millions, are maintaining the
whole ecosystem.
opposite above | Dicerca (Buprestidae) A hunting wasp
captures a jewel beetle. This specialist wasp only hunts
jewel beetles, and so also helps scientists monitor the spread
of the invasive Emerald Ash Borer Agrilus planipennis.
left | A Namaqua Chameleon catches a toktokkie desert
beetle (Tenebrionidae) in the Namib desert.