World Lion Day

On April 27th I wrote a post (and baked a cake) for International Tapir Day – it seemed relevant to celebrate the buggers that were skilfully evading my camera traps. Nearly every day is a "World <insert animal here> Day". So, I'm not going to ramble about each of them, but it turns out that apparently today is the first World Lion Day, a campaign raising awareness for the king of the savannah.

Lions, the rock stars of the feline world – just look at that hair! Okay, so maybe the glam rockers or '80s cats.

Lions (Panthera leo) are not amongst the most endangered of felines, nor are they the most obscure. They are omnipresent as a symbol of royalty and strength even in modern Western culture (e.g. my favourite film, Disney's The Lion King). However, even these mighty cats are vulnerable to threats imposed by humanity. After all, few animals escape the devastating consequences of habitat loss and fragmentation, especially animals with the extensive territorial needs and wide-ranging capabilities of lions. Additionally, a lion's mane is still a poaching trophy and the carnivores are killed when a threat to livestock.

We tend to think of lions ruling the African savannah, but there are Asian lions, too. Asian lions pertain to the same species, although they don't tend to be as large and the males have smaller, darker manes. This population is seriously threatened, with only a few hundred clinging on in Gir forest, India, which they share with their stripy cousin, the tiger (Panthera tigris).

This huge gap in their modern distribution represents the historical range reduction the species has suffered. Apart from a more widespread African distribution, during the Pleistocene lions roamed Europe as well as Asia, even reaching the Americas through the Beringia Straight (Yamaguchi et al, 2004). The extinct American lion (Panthera leo atrox, or Panthera atrox by some authorities) is thought to have been the biggest feline that has ever lived, larger than today's champion, the Siberian tiger, or any of the sabre-toothed cat species (Whitmore & Foster, 1967).

The prehistoric distribution of lions – as that of many of its contemporaries – is thought to have expanded and contracted significantly during the glacial cycles or "ice ages" of the Pleistocene. Perhaps counterintuitively, African lions may have spread and dispersed during the ice ages rather than in the warmer interglacial periods (Yamaguchi et al, 2004). This has been suggested because during the spread of snow and ice in Eurasia and North America, the tropics became much drier and so savannah and steppe type habitats spread, along with all the big mammals associated with them (Darwin, 1859; Denton, 1999).

The majority of the American and European lion populations disappeared sometime around 10,000 years ago (Turner & Antón, 1997), although they seem to have held on in the Iberian Peninsula and Eastern Europe a little longer (Sommer & Benecke, 2006). This was part of the Quarternary extinction event that killed off many large mammals. There is some debate as to the causes of this extinction event, with hypotheses including climate change and human activity. The latter suggestion is, however, very controversial, and for now it seems more likely that the climatic shift at the beginning of the Holocene deemed conditions incapable of maintaining the Pleistocene ecosystems.

Given this, a great deal of the historic reduction in the lion's geographic distribution was not a direct result of human pressure. However, humans are responsible for the recent decimation of lion populations. While true that they are greater in number than other threatened animals and are not classified as endangered, it is estimated their numbers have dropped by 30% in about 20 years (Bauer et al., 2012). That is a rapid decline. What's more, it is important to protect species' before they reach a critical point, to conserve a healthy gene pool and preserve their habitat and its ecosystem dynamics.


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Cited literature:

Bauer, H., Nowell, K. & Packer, C. 2012. Panthera leo. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.1. <www.iucnredlist.org>. 10 August 2013.

Darwin, C. (1859). Geographical Distribution (I). In The Origin of Species. 344—374. Middlesex, UK: Penguin Books Ltc.

Denton, G. H. (1999). Cenozoic climate change. In African biogeography, climate change, & human evolution: 94–114. Oxford, UK: Oxford University Press.

Sommer, R. S. and Benecke, N. (2006). Late Pleistocene and Holocene development of the felid fauna (Felidae) of Europe: a review. Journal of Zoology, 269 (1): 7–19.

Turner, A. and Antón, M. (1997). The big cats and their fossil relatives. New York, USA: Columbia University Press.

Whitmore, F. C. Jr., and Foster, H. L. (1967). Panthera atrox (Mammalia: Felidae) from Central Alaska. Journal of Paleontology, 41(1): 247-251.

Yamaguchi, N., Cooper, A., Werdelin, L., and Macdonald, D. W. (2004). Evolution of the mane and group-living in the lion (Panthera leo): a review. Journal of Zoology, 263 (4): 329–342.