Specimen of the Week: Week 105
By Emma-Louise Nicholls, on 14 October 2013
This week’s Specimen of the Week required more than the normal hour of research and writing (don’t tell the boss). Strange given it is about a species a substantial amount of the global population will have heard of. And yet on this particular area of this species, our knowledge is lacking. It is surprising how little we sometimes know about things that otherwise seem so familiar to us. The first draft of this blog resembled a taxonomic mess of proposed but unsubstantiated scientific names and both limited and shaky evidence supporting both sides of an academic argument over, whether this animal actually exists. What do I mean? Read on armchair explorer, this week’s Specimen of the Week is…
**The Cape lion**
1) This specimen is either one of the most or the least interesting specimens we have at the Museum. Let me explain… Although you may think of lions as the well-known big yellow-ish furry felines that live in prides and feature in Disney films such as Dumbo, Robin Hood and The Wild (you thought I was going to say the Lion King didn’t you), lions are actually extremely diverse. Or possibly they aren’t. There have been over 20 lion subspecies named and described, though only two of them are actually widely accepted. This cornucopia of lion subspecies has been suggested primarily based upon, it seems, geographic isolation of populations.
2) One of these (potential) subspecies is the Cape lion. Now extinct, it inhabited the southern tip of Africa, around Cape Town, hence its name. It is thought to have been the largest and heaviest of lions, with a darker mane than most African lion populations. It is widely cited that the Cape lion went extinct in 1858, with the last one seen in the wild purportedly killed by a Czech explorer.
3) There are some (many) that argue that the Cape lion is not a real subspecies, but rather a non-genetically distinct but geographically separated population of another subspecies of African lion. It’s all about molecular analysis these days and studies suggest that the haplotypes-2 and -5 (clever science speak for measuring lion-y-ness) are the same in the Cape lion as those for other individuals classified as different subspecies. Meaning they are one and the same. However, it is important to note that these studies were based on tiny sample sizes of museum specimens, the precise origins for which are not 100% verified. Therefore, scientifically speaking, there is not enough evidence to conclude that the Cape lion is a distinct subspecies. But equally, there is also not enough evidence to determine that it isn’t. Sigh.
4) How do you end up with a ‘false’ subspecies? Well, ‘back in the day’ species were named based almost solely on what they looked like. Differences in the appearance of species are often used to infer that they are not the same species. The flaw in this method comes when environmental factors alter the physical appearance of individual populations that are otherwise exactly the same. Humans for example are all the exact same species but you can have a guess as to where a person is ancestrally from based on subtle differences in our appearances. I and my ancestors for example, hail from a country with no sun. So I am pale and pasty with blue eyes and have to blink constantly in countries with high levels of incandescence. The same phenomenon occurs in lions. The Cape lion was known to have black-tipped ears and an extensive mane in comparison with the other African lion populations, but studies have shown that these aesthetic differences can be caused by habitat differences and are not necessarily caused by genetic diversity.
5) Is our Cape lion skull no longer interesting to science then? Yes of course it is, and I’m not just saying that because I work here and think it is the greatest-collection-of-all-time-that-I-currently-work-at. It is interesting and important for two primary reasons. The first is that, it has still not been fully ascertained whether the Cape lion is a distinct subspecies or not, so we’d better take care of it just in case it happens to be a rare specimen of an extinct animal. Secondly, at the very least the ‘Cape lion’ represents a population of the southern African lion that is now extinct. Whatever the reason behind differences between the Cape lion and other African lion populations, the differences were nevertheless present and this skull is one of an irreplaceable set of specimens remaining of the group. The local extinction of a species, particularly a large and numerous predator, will have had a significant impact on the ecosystem and the species it left behind, making it a significant event, of which this skull was a part.
Emma-Louise Nicholls is the Museum Assistant at the Grant Museum of Zoology