Look what’s back!
I was able to get some new photographs for Mystery Seed of the Week. In fact, I’m set for new Seed of the Week posts for the next few months while I develop some other materials behind the scenes.
Without further ado, we have some funny-shaped seeds.
Do you recognize what plant the seeds are from? If you choose to, please leave a comment with your ideas.
(New mystery seeds and Seed of the Week answers are posted on Tuesdays.)
Yesterday we introduced the lovely plant, Thurber’s cotton, Gossypium thurberi.
While I was taking photographs of the plant, I noticed some ants.
These kind of ants are called rover ants. They are not very big. What are they doing on the plant?
Here’s one in the flower. It is visiting the nectar-producing area or “floral nectary.”
The rover ants were also visiting an area under the flowers, on the sepals. Any ideas why?
Having some experience with cotton plants, IÂ realized the ants were visiting some nectar-producing areas there as well. Nectaries outside the flower proper are called “extrafloral nectaries.” See that dimpled area the ant is facing? That is an extrafloral nectary.
As you can see, the extrafloral nectaries on the plant were very popular.
Many different plants produce nectar in various extrafloral nectaries and most of them attract ants and small wasps.
The most commonly-reported reason that plants have these structures is that the nectaries attract predators and parasites, which in turn attack the eggs and larvae of plant-feeding insects they encounter.
Have you ever seen ants visiting nectaries on plants? What kind of plant was it?
After 220 mystery seeds, it is time to step back and evaluate where we want to go from here. Although seeds are incredibly beautiful and fascinating, frankly it is becoming increasingly difficult to gather new material each week. Therefore, Seed of the Week will be taking a brief sabbatical.
Some options for the future are:
Obviously, none of these ideas are mutually exclusive.
If you have any suggestions for what would be useful additions to this series, ideas for collaborations, or have comments about the different options, your input would be greatly appreciated.
For more information, see Roberta Gibson Writes.
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