Monthly Archives: September 2014
If we think of today’s red panda, our mind travels to the thick forests of the Eastern Himalayas ad South Western China, where this cute carnivore spends its days peacefully munching bamboo. But back in the Miocene, the fossil relatives of the red panda were not only much more widespread, ranging from North America to the Iberian peninsula, but they also were rather more diverse.
The living red panda, Ailurus fulgens, is the only surviving member of the family Ailuridae, and its dentition is quite specialized for the consumption of leaves, and especially those of the bamboo. Another specialization is the presence of a “false thumb” and enlarged bone in the wrist that it shares with the giant panda, and which both animals use as a help to handle bamboo shoots while feeding. But the earliest members of the family were generalist animals, with more primitive, all-purpose teeth, reflecting a more varied diet that included a lot of animal protein. Just like the living red panda, those early ailurids were smallish animals, not much larger than your average house cat. But during the Miocene, stem ailurids gave rise to a group of larger carnivores, actually rivalling a modern leopard in size: the Simocyonines.
One region of the world that has provided an unusually rich fossil record of the ailurids is, you guess it… Madrid! Here, in middle Miocene sediments in Madrid’s capital city, we have found remains of Magerictis imperialiensis, a small species still resembling the stem ailurids, and which combined the small body size of the red panda with a long, dog-like muzzle to house its primitive dentition.
But the most spectacular ailurid fossils from Madrid are those of the simocyonine Simocyon batalleri, from the Vallesian (late Miocene) site of Batallones-1.
With a shoulder height of 70 cm and a body weight of around 60 Kg, this animal was much larger than the red panda. Its dentition was well adapted for a varied diet of meat, carrion, invertebrates and even vegetable matter, and it would be a predator to reckon with if we could see it in the flesh. The problem is that it had to share the Batallones Miocene surroundings with a collection of truly fearsome competitors, from heavy bear-dogs to sabertooth cats.
In the face of such competition, discretion would be the best part of valour for Simocyon, and it would quickly climb up the nearest tree!. Its postcraneal skeleton reveals excellent arboreal abilities. In fact, it was probably one of the most refined climbers around, as revealed by the presence of a “false thumb”, an enlarged carpal bone that allowed Simocyon to grab thin branches with its forepaws and get a firm grip in the tree tops, probably beyond the reach of other carnivores such as the sabertooth cats. But the dexterous hands of Simocyon also would serve it to reach edible objects in the trees, including leaves, fruits and even bird’s eggs.
Here is a reconstruction of the skeleton of Simocyon batalleri (top), and a comparison between the bones in the palm of the hand of the giant panda (bottom left) and Simocyon (bottom right), with the radial sesamoid bone or “false thumb” marked in blue
The presence of the “false thumb” in this early relative of the red panda suggests that this feature of the ailurid hand did not originally evolve as an adaptation to feed on bamboo -in fact, the diet of Simocyon was much more like that of a dog than that of a panda!. All evidence suggests that the early ailurids developed a large radial sesamoid as an adaptation for proficient climbing, and only afterwards was this feature “recycled” by the later, more vegetarian red pandas, as an aid in handling bamboo. A nice example of evolution just “making do” with the available materials!
If I could travel back in time to the late Pleistocene of Rancho la Brea in California, I would sure try to set the controls of my time machine so as to coincide with one of the rare entrapment episodes, when the trashing of one large bison or horse trapped in the sticky asphalt attracted dozens of large, hungry predators. It has been calculated that one such episode every ten years would be enough to account for the thousands upon thousands of fossils accumulated at the site, so for most of the time life around the tarpits would be business as usual, and our trip around the area would be just like any safari in today’s African reserves -meaning that the big carnivores would be rather difficult to come across! We would probably drive for hours and see impressive herds of mammoths, horses and bison, but we would just wonder, where the carnivores are?
But if our arrival coincided with an entrapment episode, there is one carnivore we would be more likely to see than any other: the dire wolf, Canis dirus. Known from the bones of more than 1600 individuals from the site, this was obviously one of the dominant predators in the area, and it would stand its ground to such impressive competitors as the sabertooth cat Smilodon fatalis or the even larger American lion, Panthera atrox.
What did Canis dirus look like? Reading the paleontological literature I came across texts describing it as a “hyena-like wolf”, with short legs and a massive head with a powerful crushing dentition. However, a visual inspection of dire wolf fossils showed them to be perfectly wolf-like to me. In order to get a clearer idea of how the animal would look in life, I made a careful drawing of the skeleton using as main reference the descriptions, photographs and measurements made by American paleontologist John Merriam, together with my own photos of dire wolf fossils from different sites.
The result: a skeleton that showed only slight differences from that of a modern gray wolf, which can be summarized as follows: the dire wolf was on average a little larger, with a slightly larger head and feet that were a bit shorter. Those differences were clearly evident when you compared the measurements, but they were so slight that the overall visual impression when looking at the skeleton was overwhelmingly wolf-like.
Then I proceeded to add soft tissue from the inside out, starting with the deep muscles -those whose attachments leave clearest impressions on the bone- and then adding more superficial layers.
To reconstruct the animal’s fur, I used as reference the coat of its closest living relatives, that is, wild extant members of the genus Canis. In these animals, from jackals to coyotes to gray wolves, fur color patterns are variable but can be described as variations on a theme, and a very stable one, so the phylogenetic affinities of Canis dirus leave us little room for invention in terms of its coat colour.
So I think that in our time travel we would come across packs of very wolf-like animals, strong and resourceful canids that were able to thrive in an environment packed with the most dangerous competitors. Their extinction, like that of their fearsome felid enemies, is a fascinating, standing mystery.
All art published in our book “Dogs: their fossil relatives and evolutionary history”, by Xiaoming Wang, Richard Tedford and Mauricio Anton, Columbia University Press, New York 2008.
Paleoart, (at least professional paleoart) is largely an educational activity. We paleoartists are expected to show to the public, lay and specialist alike, what science knows about extinct animals. So we are very much supposed to keep our creatures behaving properly, and showing the kind of activities they were most likely to engage in. The science of paleontology has to live with enough uncertainties without us further confusing our viewers by showing unlikey behaviors in our paleo-scenes.
But when you spend some time out in the wild observing free-ranging animals, you are apt to see them doing things that defy your understanding. In fact, much of the excitement of watching wildlife is how the real animals keep forcing us to expand the limits of what we think they can or should do.
These days I was looking at some pictures from our 2006 safari to Kenya, and I found an unusual sequence of secretary bird photos. Secretary birds are supposed to walk in the savannah, alone or in pairs, scanning the grasslands for prey such as insects and small (and sometimes not so small) vertebrates. Most times I have seen them that is exactly what they were doing. But on that particular day in the Maasai Mara, a group of vultures were enjoying the last scraps of a carcass when a secretary bird entered the stage and began chasing and pestering the vultures for no apparent reason. The action continued for some time, and the more we saw it the less we understood what was happening.
At no time did the secretary bird show any interest on the carrion, nor was there any evidence that it had a nest nearby which it would need to protect. All in all, it gave us a nice show of its antics, but its ultimate motivations remained a mystery.
You can only imagine that prehistoric animals would be doing wonderfully surprising things quite often as well. As a paleoartist I have always forced myself to stick to the most statistically probable behaviors, just as my reconstructions have always been anatomically conservative. But that doesn’t mean I am not aware that life is, by its very essence, always surprising!
Being able to be a witness to such amazing scenes is another of the reasons #WhyILoveKenya
Evolution has shaped the wolf as a long-distance runner. The iberian lynx may stalk with endless patience and the brown bear ambles ponderously on plantigrade feet, but the main weapon of the wolf is its ability to run tirelessly over enormous distances. Such stamina is originally and adaptation for surveying large territories and for chasing fast prey animals to exhaustion, but it has also served as a pre-adaptation for a new challenge: to escape man’s prosecution.
The Iberian wolf lives now like an outlaw, cornered by the action of human greed, ignorance and cruelty. True, the wolf also has got friends among humans, who are not just going to sit and watch, but its enemies “play with marked cards”, taking advantage of social inertia and inherited privilege.
I try to capture the elegance of the wolf with quick, 10-minute drafts, which I force myself to quit before my pencil has time to dwell in too much detail. The strategy to defend the wolf, by contrast, has to be a labour of patience and time. Meanwhile, the wolf needs to keep trusting its sinewy legs for survival. It has to keep running while we come to the rescue. Hopefully it won’t be too late by then.
As a tiny contribution to stop the abuses against the wolf, I have signed the petition below. Will you?
Wolf biologists often use the term “scapewolf” to refer to the individual animal occupying the lowest postition in the pack’s “pecking order”. The life of that creature can get hard enough for it to leave the safety of the pack and try its luck as a lone wolf.
Today the Iberian wolf has become a sort of scapegoat or “scapewolf” for a troubled and confused Spain. The problem is that, as a species, the wolf has nowhere to go.
Back in the hopeful seventies, naturalist and filmmaker Félix Rodríguez de la Fuente managed, almost single-handedly, to change the perception that the Spanish society had of the wolf, from hateful vermin to the ultimate example of the beauty and freedom of wild nature. In those days it was only normal for people to believe that a more natural life was possible, and that we were slowly but surely heading in that direction.
Now we are in the middle of a recession which is eroding away our brighter side. A few years ago we used to say that the crisis would bring out the best in us, that we would emerge more sober and wise. Now it seems that it has been the other way round, and we see ever more selfishness, aggression and spite everywhere. And politicians, always the opportunists, take every chance to offer new victims to the people’s hatred and frustration.
Now it seems it is the turn of the wolf to be sacrificed. Spain’s livestock owners are, like everyone else, seeing their life conditions worsening all the time, and the government is unable or unwilling to offer any real solution for their problems. But it can use a scapegoat, and it readily does so, offering to kill an unsustainble proportion of the already cornered Iberian wolf population. For a handful of votes, Spanish authorities are more than willing to renounce all pretense of a conservation policy, at the same time going against the spirit of all European environmental regulations.
We have learned the hard way not to expect much from our politicians. And if we still hope to leave a inhabitable world to our children’s children, it is up to the citizens to defend that hope.
Here is one opportunity for all of us as citizens to at least say no to mindless abuse and destruction. We can say no to the unjustifiable, government-sanctioned killing of 190 wolves in Northern Spain. I still believe it is possible for us to live with nature and not against it. In fact it is the only way, if we want a semblance of civilization to endure for more than a couple generations. Other things are harder: just SIGN!