Plants Develop Weapons in Struggle for Selection

Original Article: First evidence of plants evolving weaponry to compete in the struggle for selection
Source: ScienceDaily.com
Date: March 20, 2014

Image of the Milkweed plant from www.isciencetimes.com

Summary: A team of scientists in Argentina, led by Dr. Andrea Cocucci (from the Institution Multidisciplinario de Biologia Vegetal) have been studying a species of milkweed that is found in tropical climates. They have been led to the conclusion that plants have begun to develop weapon-like structures in an attempt to outfight other plants in natural selection. Plants like milkweed reproduce by pollinators such as birds or insects which can lead to competition to use those pollinators and confrontations between the plants. Milkweed, in specific, hooks sacks filled with pollen onto birds and other pollinators which are unconsciously dropped pollinate. Sometimes, a couple of these sacks can get entangled, which is what this team thinks is the potential course of the confrontation. Their research showed that the sacks have developed biologically-unnecessary horns, but they seem to serve the purpose of preventing the sacks from tangling together.

Image of the Milkweed's Pollination
Sack with newly-developed horns

N.O.S. Themes:

• Science is based on evidence- evidence showed the milkweed plant developed horns on its pollination sacks
• Role of credibility- the research came from the Institution Multidisciplinario de Biologia Vegetal in Argentina
• Importance of repeatability- it is important they make this "discovery" more times amongst the milkweed and amongst other plant species before they jump to any conclusions
• Role of curiosity/motivation- the scientists were interested as to why these horns were developed so the researched further to find out why

Thoughts: I think it is interesting how plants even have to compete to reproduce- we generally just associate that with mammals or reptiles (for example how bears will fight for a mate). I am wondering if they have noticed these types of patterns in other plants as well? If so- why kinds of mutations and why? I am curious because I tried searching for other articles, but I couldn't find anything.

Published: March 22, 2014 – 2:22pm
By: Julia Garbuz (Hour 1)