Parasitic non-pollinators in VS .NET

Encode Quick Response Code in VS .NET Parasitic non-pollinators

Just as some plants avoid giving a reward, some animals take the reward but don t provide any pollination services Think back to the 10-inch-long flower Many flowers have deep (though not quite so extreme) nectar sources, which make them inaccessible to insects with short proboscises

Some insects have developed a clever solution to this problem: They just hold the base of the flower, chew a hole, and slurp out the nectar, never getting anywhere near the pollen In this case, the insect is a parasite of the flower As the species co-evolve, the plant species is selected to have less-chewable flowers, and the insect is selected to be better able to chew its way to the nectar

Plants that share pollinators have to compete to attract them This competition among plants introduces another place for selection to operate Plants that rely on the same pollinators, for example, will be selected to flower at different times By flowering in a narrow window of time, a plant increases the chance that its pollen will go to an individual of the same species Similarly, a species of plant that flowers at a time when other species don t has better access to pollinators and, as a result, is more likely to leave descendents

If seeds are light and small, they can be dispersed by wind The problem with this system is that the plant has to make a lot of seeds, because most of them end up in the wrong place Having an animal disperse your seeds can solve this problem, though it may introduce others (the animal might eat your seeds) Animals can move larger seeds, and they provide a bit more specificity in where the seeds end up If a particular bird is eating a particular fruit, that bird is known to visit places where that particular kind of plant can grow and may end up depositing the seeds in a similar habitat This system is how mistletoe seeds get dispersed Mistletoe is a parasitic plant that grows on other plants Mistletoe fruit is eaten and the seeds dispersed by perching birds, which conveniently deposit the seeds right onto another potential host plant The fruit is the lure that gets the birds to eat the seed Not all relationships that result in seed dispersal are mutualisms, of course Some plants are very good at getting animals to disperse their seeds without giving any reward If you ve ever had to pull seeds out of your socks or off your dog after a hike, you know exactly what I m talking about Some plants have evolved quite clever mechanisms that allow their seeds to be attached to animals Not all seed or fruit eaters disperse the seeds; some just digest those as well, setting up another co-evolutionary interaction that has resulted in plants producing seeds with toxins and animals developing the ability to cope with these toxins

This mutualism is my favorite one, occurring between the bullthorn acacia (Acacia cornigera) and the ant Pseudomyrmex ferrugiea The bullthorn acacia has large hollow thorns where ants live, and it produces nectar (not associated with flowers) and protein-rich structures that the ants eat The ants patrol the plant and sting anything that tries to nibble or land on it, and they clear the ground under and around the plant, killing any plants that might compete with the host acacia Not such a big deal, right Wrong The bullthorn acacia is unusual Other acacias don t produce extrafloral nectaries; they don t produce the protein structures, which have no known function other than to feed the ants; and they re poisonous, producing chemicals to defend against herbivores The bullthorn acacia doesn t have these characteristics because it doesn t need them; it has the ants instead And let me tell you, these ants really hurt when they sting I know because I checked personally And I m not the only person who thinks so The Schmidt Sting Pain Index yes, there really is one; you can see for yourself by going to http://scientiaestpotentiablogspotcom/2006/06/ schmidt-sting-pain-indexhtml rates them at 18 (a bald-faced hornet gets a 2) and describes the pain as A rare, piercing, elevated sort of pain Someone has fired a staple into your cheek Someone there must have been stung, too, which just goes to prove the lengths to which scientists will go to collect data