Recent research in Hluhluwe-Umfolozi Park, KwaZulu Natal, South Africa puts this predilection into an evolutionary perspective. “Many fleshy fruits that we enjoy, like mangoes and avocados, once evolved to be eaten and dispersed by elephant-like creatures that are now extinct.” says Åsa Hemborg, author of the study published in the African Journal of Ecology, “In the world today, only Africa and Asia can show examples of how these powerful browsers affect the trees they feed on. The sweet and fleshy Marula fruits evolved to attract the most powerful browser on the savannah - the African elephant.”
In this, the Marula trees are very successful “In fact, elephants are crazy about them!” observes Dr Hemborg “They spot the Marulas from far and walk long distances to feed on fruits, foliage and bark.” The research shows that the female Marula suffers a higher risk than the male tree of being destroyed and perhaps killed by elephants. “There is a conflict of interest experienced by female trees when the disperser also has the potential to seriously damage or kill the tree.”
Interestingly, evolution has not provided the female tree with tougher branches, as their branch resistance was similar to that of male plants. This suggests that it may be hard to resist elephant attacks by strength alone. Instead, the selective pressure of browsing may promote the evolution of trees with good resprouting ability.
Although mega-herbivores such as the elephant have now gone from most parts of the planet, study of unisexual trees such as the Marula can help shed light on the shape and form we see in trees today because only females live with the risk of being destroyed by the same animal that she seeks to attract as a disperser for her fruits.
Davina Quarterman | alfa
Global threat to primates concerns us all
19.01.2017 | Deutsches Primatenzentrum GmbH - Leibniz-Institut für Primatenforschung
Reducing household waste with less energy
18.01.2017 | FIZ Karlsruhe – Leibniz-Institut für Informationsinfrastruktur GmbH
A Swedish-German team of researchers has cleared up a key process for the artificial production of silk. With the help of the intense X-rays from DESY's...
For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.
According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
24.01.2017 | Physics and Astronomy
24.01.2017 | Life Sciences
24.01.2017 | Health and Medicine