West and Central African lions are genetically different from those in East and southern Africa

The study, from which the results were published in the Journal of Biogeography, was conducted by a consortium of researchers from a number of different universities.

Genetically different

The outcome of their research suggests that lions from West and Central Africa are genetically different from lions in East and southern Africa. The researchers analysed a region on the mitochondrial DNA of lions from all over Africa and from India, including sequences from extinct lions such as the Atlas lions in Morocco. Surprisingly, lions from West and Central Africa seemed to be more related to lions from the Asiatic subspecies than to their counterparts in East and southern Africa.

Previous research has already suggested that lions in West and Central Africa are smaller in size and weight, have smaller manes, live in smaller groups, eat smaller prey and may also differ in the shape of their skull, compared to their counterparts in East and southern Africa. However, this research was not backed by conclusive scientific evidence. The present research findings show that the difference is also reflected in the genetic makeup of the lions.

Barriers for dispersal

The distinction between lions from West and Central Africa and individuals from East and southern Africa can partially be explained by the location of natural structures that may form barriers for lion dispersal. These structures include the Central African rain forest and the Rift Valley, which stretches from Ethiopia to Tanzania and from the Democratic Republic of Congo to Mozambique. Another aspect explaining the unique genetic position of the West and Central African lion is the climatological history of this part of the continent.

It is hypothesised that a local extinction occurred, following periods of severe drought 40,000 to 8,000 years ago. During this period, lions continuously ranged deep into Asia and it is likely that conditions in the Middle East were still sufficiently favourable to sustain lion populations. The data published in the Journal of Biogeography suggest that West and Central Africa was recolonised by lions from areas close to India, which explains the close genetic relationship between lions from these two areas.

Declining population

There are thought to be some 1,700 lions left in West and Central Africa, which is less than 10% of the total estimated lion population in Africa. Lions in West and Central Africa are declining and are under severe threat due to the fragmentation or even destruction of their natural savannah habitat, the depletion of prey and retaliatory killing by livestock owners. The West and Central African lion is currently categorised as 'Regionally Endangered', according to IUCN criteria. Recent surveys in a large number of Lion Conservation Units in this region were, in fact, not able to confirm the presence of lions.

Other carnivore species, such as the wild dog and the cheetah, have become almost extinct in the region, with small populations surviving in Niger, Benin and Burkina Faso. These populations also appears to be struggling, suffering primarily from habitat loss and degradation, and conflict with local people.

Conservation

To save the last remaining large carnivores in this region, a new initiative has been launched: the 'Large Carnivore Initiative for West and Central Africa'. This initiative is supported by a large number of conservation organisations. Insights into the geographic pattern of genetic variation within a species can contribute significantly to the field of wildlife conservation. The patterns described in this publication should have consequences not only for in situ wildlife management, but also for management of zoo populations and captive breeding programmes.