On a BBC TV programme about mongooses, there was a statement that banded mongooses cleaning warthogs is the only example of a symbiotic relationship between two mammal species.

Leaving aside the question of whether cleaning is in fact a symbiotic relationship, is this true?  I'm sure I've heard of other mutually-beneficial relationships between two species of mammals, but can't recall any specifics.

Hi Kate,

Sorry about the delay in replying to your email. The reason for this probably lies in the fact that none of us can think of another example either! Although, some might argue that domestication would be a sybiotic relationship: The population(s) of wolves that attached themselves to humans found an advantage in doing so, as did the human population(s) that accepted this deal...

Hope this helps,

Carlos.

I think the question comes down to nomenclature. There are a variety of different forms of symbiosis, which can include parasitism (one party benefits at the cost of damage to the other), commensalism (one party benefits and the other is neither benefited, nor harmed) and mutualism (where both parties benefit). There's also amensalism, where one party impedes the success of another party, but derives no benefit from doing so. Each of these represent different forms of symbioses between different species.

I think it's true to say that there are a fairly broad range of mutualistic relationships out there, from fleeting transitory arrangements, to composite organisms. With regards the extreme scale of mutualism, the relationship typically described when many people used the word 'symbiosis', we think in terms of those such as that between Swollen Thorn Acacia trees and the ant species that live within them; or your choice of nectar producing plant + insect species used for pollen dispersal; or even more intertwined relationships in composite organisms such as corals (coral + algae) and lichen (fungi + algae). 

At this level, representing a physical and physiological interaction, I am unaware of any such symbioses between mammals.

There are plenty of bird-mammal mutualisms however, one example being the relationship between the Honey Guide bird and the Honey badger (video) where the bird leads the badger to honey (benefit to badger) and the badger tears apart the hive (benefit to bird, which can now access honey).

Of course, what would happen if we removed one, or the other, of these organisms from the picture? In the strongest forms of mutualism (sometimes called obligate), we would perhaps expect one or both of the organisms to die. It's doubtful that there are any such mammal species with such a relationship, but I'm open to suggestions from other biologists here.

In answer, I think you've cited a fairly good example of a mutualism, but you need only look for close, mutually beneficial relationships between mammals to see other forms of mutualistic symbioses.

Last edited by Jim Caryl (24th Feb 2010 15:26:39)

Not two mammals, but I saw this today and felt it relevant to post here:

http://news.bbc.co.uk/earth/hi/earth_ne … 534844.stm

It seems as though warthogs are happy to be groomed by just about anything; and who can blame them.

I remember a great example of co-operating mammals, described in this paper:

Minta, Steven C., Kathryn A. Minta and Dale F. Lott.  1992.  Hunting Associations between Badgers (Taxidea taxus) and Coyotes (Canis latrans).  Journal of Mammalogy 73(4): 814-820.

The abstract is:

Coyotes (Canis latrans) associating with badgers (Taxidea taxus) appeared to hunt Uinta ground squirrels (Spermophilus armatus) more effectively than lone coyotes. Coyotes with badgers consumed prey at higher rates (P = 0.09) and had an expanded habitat base and lower locomotion costs. Badgers with coyotes spent more time below ground and active (P = 0.02), and probably had decreased locomotion and excavation costs. Overall, prey vulnerability appeared to increase when both carnivores hunted in partnership. Complementary morphological adaptations and predatory strategies, interspecific tolerance, and behavioral flexibility allowed them to form temporary hunting associations. The following ecological circumstances may have increased the likelihood of this interaction in our study area: relatively high densities of predators and prey; relatively long-lived predator populations; a vegetative structure that impeded solitary hunting by coyotes; a high connectivity of prey burrows that decreased hunting success of badgers; an absence of interaction with humans; a stressful physical environment.