Mutualistic Symbiotic Relationships of the Maned Wolf
, Courtesy of Tambako The Jaguar (flickr)
When thinking of the natural world, we often focus on the fight for survival, the battle of prey versus predator or the competition for available food or territory. And yet there are many examples of different species working together for the benefit of both. This is known as a mutualistic symbiotic relationship.
In the most basic sense, a symbiotic relationship is the interaction of two species (plants or animals). There are several types of symbiotic relationships depending on how the two species are affected by this relationship. In a mutualistic symbiotic relationship, both species gain an advantage from their interaction.
Symbiotic Relationships Involving the Maned Wolf
The maned wolf can be found in the grasslands of parts of South America, particularly the vast tropical savannas of Brazil known as the Cerrado.
In some ways, the maned wolf resembles a fox with extremely long legs, but it is not considered to be a fox or a wolf. Nor is it a dog, coyote or a jackal. Although it is in the same family as these other canines, it is not closely related to any of them.
Unlike most large canines, the maned wolf does not hunt in packs. It feeds on rodents, birds and sometimes fish. But a major portion of the maned wolf’s diet consists of plants.
Among the vegetable matter the wolf eats, lobeira, also known as wolf apple, is one of its favorites. The wolf apple comes from a flowering shrub. The fruit itself is yellow with some red and is similar to a large tomato.
So, how do the the maned wolf and lobeira help each other out? To start with, the fruit of the lobeira plant is a major part of the maned wolf’s diet. But the wolf eats many things, both plants and animals.
When the maned wolves were first introduced to zoo environments they were feed strictly on meat. On this diet, the wolves frequently developed bladder stones. When fruits and vegetation were placed back on the menu, this problem disappeared. So now we see a benefit of plants in general to the maned wolf’s diet, but it is unknown if the lobeira fruit plays a major role in this effect to the wolves in the wild.
The need for plants in the maned wolf’s diet seems clear, but what about the lobeira fruit. Is there any distinct advantage received by eating this fruit, that is not available from other sources?
There may be. Many believe that ingesting the lobeira fruit protects the wolf from a parasite called the giant kidney worm, which can be fatal. Although it has not been proven that the fruit does protect the wolf from the worm, there is evidence which suggests it might.
Before we go on, let’s look at the relationship of a maned wolf containing a giant kidney worm, and the worm itself. This is also a symbiotic relationship known as parasitism, in which only one member of the association benefits, whereas the other is harmed. The wolf gains no advantage from being a host to the worm, and may die due to it.
The wolf contracts the worm by consuming small prey which contains a larval form of the worm. When the parasite finds its way into the larger animal it grows into the adult form, becoming up to three feet long.
Thus far, the relationship between the maned wolf and lobeira plant seems a little one sided. So let’s see what benefit the lobeira plant receives from this relationship.
The lobeira seeds that have passed though the wolf and are deposited, have a much higher germination rate then those that don’t. The wolf caries the seeds to locations throughout its territory, and in turn broadens the territory of the lobeira plant.
But this description is an oversimplification of the the process. The whole story requires the introduction of another participant revealing a symbiotic triad.
The maned wolf often defecates on the nests of leaf cutter ants. The ants use the dung to fertilize their fungus gardens. The seeds are later moved outside the nest. This greatly increases the germination rate of the seeds.
So the wolf helps the ants by providing fertilizer for the fungus gardens, and the ant reciprocates by seeing to it that the wolf’s favorite food is in great abundance in the future.
And the greater seed yield is a service the ants preform not only for the wolf, but also for the lobeira plant.
What is unclear to me is if the ant receives any direct benefit from the fruit itself. If it does not, this constitutes another type of symbiotic relationship called commensalism in which one organism benefits from the relationship, and the other is not significantly helped or harmed.
When we see the complex interdependence of different species on earth, it is easy to get a deeper sense of the delicate balance which exists between them. It takes only a slight shift to threaten an entire ecosystem.
The maned wolf is now an endangered species, and close to being threatened due to reduction of its habitat from agricultural development such as soybean production and the expansion of cattle ranching.
The issues surrounding mankind’s interaction with the environment are not always simple ones. We need to eat, we need to provide homes for ourselves and we need to make a living. Our activities are not always beneficial to other species.
Because of the ability to impact our world in so many ways, we ultimately have a symbiotic relationship with all life. The challenge for us is to, whenever possible, find a way to make it a mutualistic one.
Check back for more fascinating examples of Mutualistic Symbiotic Relationships. Others will be added as time permits.