A report insisting that man has been responsible for the extinction of most to many of the megafauna. Entirely true of course, the big animals in any particular part of the world disappeared soon after man turned up. This is true of North America, when those Indians who so revere nature arrived, true of New Zealand, when those Maori who so revere nature turned up, true of Mauritius when those white boys who don’t give a proverbial about nature turned up. Big animals are just tonnes of meat on the hoof to those hunter gatherers who so revere nature.
The report then goes on to tell us that it’s likely enough that in a couple of centuries or so the largest land animal left will be the cow:
The cow could be left as the biggest land mammal on Earth in a few centuries, according to a new study that examines the extinction of large mammals as humans spread around the world.
The spread of hominims – early humans and related species such as Neanderthals – from Africa thousands of years ago coincided with the extinction of megafauna such as the mammoth, the sabre-toothed tiger and the glyptodon, an armadillo-like creature the size of a car.
It’s unlikely that humans wiped out the sabre-tooth, rather they wiped out its prey. But, you know:
Since the late Pleistocene, large-bodied mammals have been extirpated from much of Earth. Although all habitable continents once harbored giant mammals, the few remaining species are largely confined to Africa. This decline is coincident with the global expansion of hominins over the late Quaternary. Here, we quantify mammalian extinction selectivity, continental body size distributions, and taxonomic diversity over five time periods spanning the past 125,000 years and stretching approximately 200 years into the future. We demonstrate that size-selective extinction was already under way in the oldest interval and occurred on all continents, within all trophic modes, and across all time intervals. Moreover, the degree of selectivity was unprecedented in 65 million years of mammalian evolution. The distinctive selectivity signature implicates hominin activity as a primary driver of taxonomic losses and ecosystem homogenization. Because megafauna have a disproportionate influence on ecosystem structure and function, past and present body size downgrading is reshaping Earth’s biosphere.
They do make that point that the cow might end up being the largest land mammal. In which is an interesting point.
For the cow is a species created by man. Derived from the aurochs (possibly slightly different species/sub-such to give us the zebu and taurine types of cows) it didn’t exist before the domestication event. So, we created it. And it’s also the dominant large land mammal. Why? Because human beings find it useful. That’s why we farm it.
OK, so, you’d like to preserve those other large land mammal species? You’d better get on with making them useful to humans then, hadn’t you? Because something not of use isn’t going to get exploited and no exploitation means no continued existence.
Sure, exploits can be of different types. There’re certainly people who will pay well to stand and gawp at an elephant. Sadly though, not enough to support the herds of today – that we know as those herds are being thinned. So, we want something more, something that makes elephants more valuable.
At which point of course we should be trading ivory and eating elephant steaks. Because that makes elephants more valuable to humans and thus we’ll have more elephants.
That is, the only reason you can be against ivory trading is because you want elephants to become extinct. Well done you.