Bull horn acacias provide nutrients and housing for acacia ants in return for Bulls horn acacia trees have large hollow thorns that are occupied by " Symbiotic Plant-Ant Mutualism: Biomimetic ideas for Outsourcing in Biz. Several species of acacia like Acacia cornigera, Acacia collinsii, and Acacia drepanolobium have a symbiotic relationship with the ants (like Pseudomyrmex. Pseudomyrmex ants and Acacia host plants join efforts to protect their mutualism The indirect defence that is achieved through an ant-plant mutualism can protect nectar (EFN) represents an important plant trait to nourish symbiotic ant colonies. . Extrafloral-nectar-based partner manipulation in plant-ant relationships.
The more diverse of the two clades is inferred to have arisen in the Late Miocene in northern Mesoamerica, and subsequently expanded its range throughout much of Central America. The other lineage is estimated to have originated in southern Mesoamerica about 3 Myr later, apparently piggy-backing on the pre-existing mutualism.
Acacia Tree Ants
Comparative studies of the two lineages of mutualists should provide insight into the essential features binding this mutualism. Introduction An outstanding question in the study of multispecies symbioses concerns the influence of phylogeny and biogeography on the origin, evolution and functional dynamics of such interactions. By considering multispecies interactions in a phylogenetic and geographical context, we gain insight into factors propelling, impeding or modifying the associations, and the extent to which selective pressures vary across different landscapes and phylogenetic lineages [ 1 — 6 ].Acacia Trees and Acacia Ants
Phylogenies also allow instances of convergent evolution of symbiotic associations to be more rigorously identified and analysed [ 67 ].
In this system, the ants receive nesting space in the form of swollen stipular thorns, and food from extrafloral nectaries and specialized leaf-tip food bodies Beltian bodies.
The ants in return protect their host plant from herbivores and competing plants, by patrolling aggressively, removing or repelling intruders and clipping competing vegetation [ 1619 — 23 ]. The system has also been invaded to a limited degree by parasitic non-protective ants [ 2425 ], although certain features of the ants and plants appear to constrain this [ 2326 — 28 ]. There are aggressive Pseudomyrmex associated with other domatia-bearing plants, such as Triplaris and Tachigali [ 111329 ], but most species in this genus have very different habits: Similarly, other species of Vachellia do not display the constellation of mutualism-associated traits—inhabitable swollen thorns, food bodies and enlarged extrafloral nectaries—shown by the Mesoamerican ant-acacias [ 20 ].
Pseudomyrmex ferruginea - Wikipedia
In this study, we employ a phylogenomic approach, ultraconserved element UCE sequence capture [ 3132 ] and comprehensive taxon sampling to address the following questions: More specifically, do phylogenomic data support recent inferences [ 1323 ], based on Sanger sequencing, that the acacia ants evolved more than once?
Where and when did they originate? By what sequence of events did they come to occupy much of Mesoamerica?
Although our focus is on the ants, we take into account the available information about the phylogeny and distribution of the plant partners. Our findings highlight a strong biogeographic component to the evolution of this system, and potent forces of convergent evolution in the ants.
These results generate additional questions about the selective forces driving and restraining this iconic mutualism. Such a shelter is also called domatia. As they live in the thorns, the ants are protected from difficult climatic conditions. Food The acacia gives the necessary nourishment to the ants which live on it, as it provides them with: Beltian Bodies The Beltian bodies are red in color, and are found on the tips of the leaflets of acacia.
The Beltian bodies are a great source of nutrients as they are rich in: Proteins Lipids It is believed that the Beltian bodies were developed as a result of the relationship between the ants and the acacia tree, which implies that the tree produces the nutrient-rich bodies only to feed the ants. Nectar Nectaries are found towards the base of the petioles of the acacia tree. The ants feed on the sweet carbohydrate-rich nectar secreted by the nectaries, and gain the energy that they require to sustain their lives.
How is the Acacia Tree Benefited In return for the food and shelter that the acacia provides, the ants protect it.
Relationship Between Acacia Tree and Ants
This can be studied in three parts: Protection Against Insects The ants do not harm the acacia tree, but there are several insects which might harm wither the leaves, rot the flowers, etc. The ants ward off all other insects which try to occupy the acacia, thus protecting the tree from any damage.
Defense Against Herbivores Apart from the insects, the acacia also faces a threat from herbivores. We recently discovered that PR-proteins such as chitinases, glucanases, peroxidases and thaumatin-like proteins are also functioning in the protection of extra-floral nectar EFN of Mexican Acacia myrmecophytes.
These plants produce EFN, cellular food bodies and nesting space to house defending ant species of the genus Pseudomyrmex. More than 50 PR-proteins were discovered in this EFN and bioassays demonstrated that they actively can inhibit the growth of fungi and other phytopathogens.
Although the plants can, thus, express PR-proteins and secrete them into the nectar, the leaves of these plants exhibit reduced activities of chitinases as compared to non-myrmecophytic plants and their antimicrobial protection depends on the mutualistic ants.
When we deprived plants of their resident ants we observed higher microbial loads in the leaves and even in the tissue of the nectaries, as compared to plants that were inhabited by ants. The indirect defence that is achieved through an ant-plant mutualism can protect plants also from infections.