Wednesday: 20 July 2005
Here’s an idyllic little pastoral scene. Patient shepherds tending their flocks, pausing occasionally to lick the honeydew off their backs. Do you hear panpipes in the distance?
This is one of the types of symbiosis, a mutualism where both parties benefit, that a lot of people are familiar with. I found this one prospering on a stem of New York Ironweed, Vernonia noveboracensis, near the growing tips. There are a great many aphid species, and I have no idea what these are. The little winged jobs are the adults, and will fly off to another plant. The fat little pear-shaped ones are probably females reproducing parthenogenetically - dropping baby pregnant females who themselves are often dropping smaller baby pregnant females, sometimes a line of increasingly smaller grandmothers, mothers, and daughters.
Aphids are plant suckers, and they have the stylet to prove it. They insert this mouthpart directly into the phloem of a favored plant. They don’t even have to suck - the pressure of the sugar water in the phloem pumps the plants hard earnings directly into the aphid. Under the right caresses, the aphid will produce a drop of “honeydew”, which the ants will suck up and then transport back to the colony.
There are a huge number of species of ants, and quite a number in several genera that practice this symbiosis between ants and aphids. Not being a myrmecologist, I will have to remain unenlighted about the identity of these. The caste that is guarding and harvesting the honeydew will rush back to the nest and regurgitate their stash into another caste, the repletes, that hang from the ceilings of the nests. These will then act as reservoirs for all the ants in the colony to tap for this marvelous treat which has been secreted, consumed, regurgitated, and dripped. YUM!
There’s a great little story about botanists who study the liquid in the plant phloem. The products of photosynthesis run through this plumbing to all parts of the plant. Investigators would place an aphid on a plant, let it sink its stylet into the phloem, and then snip the hapless insect away from its stylet. This left a natural pipe tapped directly into the phloem, which dripped the fluid which could then be collected for analysis. Of course it also left a sad little aphid with no mouthparts, but hey, it’s all for science.
Here’s a great site on aphids, and another one for ants.
This is one of the types of symbiosis, a mutualism where both parties benefit, that a lot of people are familiar with. I found this one prospering on a stem of New York Ironweed, Vernonia noveboracensis, near the growing tips. There are a great many aphid species, and I have no idea what these are. The little winged jobs are the adults, and will fly off to another plant. The fat little pear-shaped ones are probably females reproducing parthenogenetically - dropping baby pregnant females who themselves are often dropping smaller baby pregnant females, sometimes a line of increasingly smaller grandmothers, mothers, and daughters.
Aphids are plant suckers, and they have the stylet to prove it. They insert this mouthpart directly into the phloem of a favored plant. They don’t even have to suck - the pressure of the sugar water in the phloem pumps the plants hard earnings directly into the aphid. Under the right caresses, the aphid will produce a drop of “honeydew”, which the ants will suck up and then transport back to the colony.
There are a huge number of species of ants, and quite a number in several genera that practice this symbiosis between ants and aphids. Not being a myrmecologist, I will have to remain unenlighted about the identity of these. The caste that is guarding and harvesting the honeydew will rush back to the nest and regurgitate their stash into another caste, the repletes, that hang from the ceilings of the nests. These will then act as reservoirs for all the ants in the colony to tap for this marvelous treat which has been secreted, consumed, regurgitated, and dripped. YUM!
There’s a great little story about botanists who study the liquid in the plant phloem. The products of photosynthesis run through this plumbing to all parts of the plant. Investigators would place an aphid on a plant, let it sink its stylet into the phloem, and then snip the hapless insect away from its stylet. This left a natural pipe tapped directly into the phloem, which dripped the fluid which could then be collected for analysis. Of course it also left a sad little aphid with no mouthparts, but hey, it’s all for science.
Here’s a great site on aphids, and another one for ants.
