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
Waste in the water – New purification techniques for healthier aquatic ecosystems
24.07.2018 | Eberhard Karls Universität Tübingen
Plenty of habitat for bears in Europe
24.07.2018 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig
There are currently great hopes for solid-state batteries. They contain no liquid parts that could leak or catch fire. For this reason, they do not require cooling and are considered to be much safer, more reliable, and longer lasting than traditional lithium-ion batteries. Jülich scientists have now introduced a new concept that allows currents up to ten times greater during charging and discharging than previously described in the literature. The improvement was achieved by a “clever” choice of materials with a focus on consistently good compatibility. All components were made from phosphate compounds, which are well matched both chemically and mechanically.
The low current is considered one of the biggest hurdles in the development of solid-state batteries. It is the reason why the batteries take a relatively long...
New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference
Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
17.08.2018 | Event News
08.08.2018 | Event News
27.07.2018 | Event News
21.08.2018 | Power and Electrical Engineering
21.08.2018 | Life Sciences
21.08.2018 | Medical Engineering