Species → Black rhinoceros
Black rhinoceros
Diceros bicornis
What if it disappeared?
Impact ModerateWithout black rhinos to swallow and carry them off, camel-thorn seeds stay beneath the tree that produced them instead of spreading elsewhere — and they germinate less successfully, producing weaker seedlings than those that would have passed through the rhino's gut.
DocumentedDetail
Jones et al. (2025). Endozoochory by Black Rhinoceroses Enhances Germination of a Key Arid Savanna Tree Species. Ecology and Evolution.
This study — the first direct experimental evidence of a mutualistic relationship between the black rhinoceros and this key arid-savanna tree — compares seeds that passed through the rhino's gut with those that fell directly to the ground beneath the tree: gut passage markedly improves germination and produces more older, resilient seedlings. Without rhinos, every seed would end up in the less favorable of the two groups.
In fenced southern African reserves without elephants, the black rhino is the largest herbivore left able to carry seeds over long distances and disturb woody vegetation — its disappearance would leave vegetation there to develop without that large disperser, more so than elsewhere.
ExtrapolatedDetail
Extrapolation à partir de Jones et al. (2025) et de la littérature sur le rôle des mégaherbivores en l'absence d'éléphants dans les réserves clôturées.
Fenced reserves in southern Africa that lack elephants rely more heavily on the black rhinoceros as their sole large seed disperser and disturber of woody vegetation — a partial substitute role never directly quantified, but plausible given its size and diet.
What's missing to confirm it: The true extent of this substitute role for the elephant, in reserves that lack one, has not been directly measured.
Over a century, this loss of dispersal would compound across generations of camel-thorns, a slow-growing tree: fewer resilient young trees would replace the aging ones, and the stand would gradually thin out in reserves where the black rhino had been the main disperser.
HypothesisOver a thousand years, camel-thorns could become rare, or vanish in places, across savannas where the black rhino carried most of the dispersal load — a gap other animals would only partly fill, permanently changing the character of these arid savannas.
HypothesisDocumentation
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IUCN Red List — Diceros bicornis, statut et population
Accessed August 7, 2026
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Jones et al. (2025) — Endozoochory by Black Rhinoceroses Enhances Germination, Ecology and Evolution
Accessed August 7, 2026
Last verified: August 16, 2026