homehome Home chatchat Notifications


Extinct megafauna were "engineers" that shaped Central and South American ecosystems

Big animals are important, and they've been important for a long time.

Matt Williams
January 19, 2022 @ 2:31 pm

share Share

Megafauna comprises large, often charismatic animals. They’re usually the first thing that comes to mind when we think of wildlife conservation. Think elephants, rhinos, giant pandas, and tigers.

There is also an abundance of extinct megafauna in the fossil record, such as mammoths, sabre-toothed cats, and dire wolves. Extinct megafauna is not just a fascinating insight into the past– their existence shapes aspects of current ecosystems in interesting ways. For instance, a new study has found evidence that extinct megafauna were important drivers of ecosystem geography in Central and South America.

Megafauna ecology

Glyptodon is an example of extinct South American fauna – a relative of the armadillos. Credits: Pavel Riha / The Conversation.

Modern megafauna animals are often described as ecosystem engineers and keystone species for the important role they have in shaping their surrounding environment. Elephants, for example, are the largest land animals in the world, with the males weighing in at up to 7 tons. They shape their environment in a number of significant ways, including maintaining grasslands and spreading plant seeds. While different megafauna animals have different impacts on the environment, they all play an important role. So, how did animals that lived in the past affect their environment?

This new study sheds some light on that question.

What the new research found

The paper focuses on the Neotropical realm — consisting of tropical Central America and all of South America. The researchers wanted to know how much of the variability in plant traits and ecosystem geography could be explained by extinct megafauna – defined by the authors as extinct mammalian herbivores weighing over 50kg. What they found was that “extinct megafauna left a significant imprint on current ecosystem biogeography”.

The authors found that many of the plant traits that they studied were significantly influenced by the presence of megafauna. These plant traits included wood density, spines on the leaves for defence, leaf size, and more. These findings mean that extinct megafauna ecology is an incredibly important component to understanding plant evolution – one which has been “largely neglected in the ecological literature” according to the authors.

They also found that – like modern elephants – extinct megafauna also likely had a role in maintaining grasslands. They discuss how the extinction events of megafauna may have played a significant role in the shift from grassland to forest ecosystem that have occurred in South America, and state that “megafauna extinctions could largely explain the current prevalence of forests in the continent”.

The paper was published in Nature Communications on 10 January 2022.

share Share

Climate Change Is Breaking the Insurance Industry

Climate related problems, from storms to health issues, are causing a wave of change in the insurance industry.

Neanderthals Crafted Bone Spears 30,000 Years Before Modern Humans Came In

An 80,000-year-old spear point rewrites what we thought we knew about Neanderthals.

Ancient Chinese Poems Reveal Tragic Decline of Yangtze’s Endangered Porpoise

Researchers used over 700 ancient Chinese poems to trace 1,400 years of ecological change

A Soviet shuttle from the Space Race is about to fall uncontrollably from the sky

A ghost from time past is about to return to Earth. But it won't be smooth.

The world’s largest wildlife crossing is under construction in LA, and it’s no less than a miracle

But we need more of these massive wildlife crossings.

The Fat Around Your Thighs Might Be Affecting Your Mental Health

New research finds that where fat is stored—not just how much you have—might shape your mood.

New Quantum Navigation System Promises a Backup to GPS — and It’s 50 Times More Accurate

An Australian startup’s device uses Earth's magnetic field to navigate with quantum precision.

Japan Plans to Beam Solar Power from Space to Earth

The Sun never sets in space — and Japan has found a way to harness this unlimited energy.

Could This Saliva Test Catch Deadly Prostate Cancer Early?

Researchers say new genetic test detects aggressive cancers that PSA and MRIs often miss

This Tree Survives Lightning Strikes—and Uses Them to Kill Its Rivals

This rainforest giant thrives when its rivals burn