Lucretia is latest member of our chicken flock (hospice) to die. RIP Lucretia (Lucy). Lucretia was a Shaver Brown with plumage colour in reverse of our other shavers. She was an older hen whose eggs had characteristic rough, thin shells. She was (ultimately) killed by egg peritonitis, a nasty condition where the yolk of the egg is dislodged from the oviduct into the abdominal cavity causing a massive infection. Shavers are bred to be a super-layers who (so we are told by the vet) often suffer egg-laying related fatalities when they are older, instead of successfully undergoing chicken-menopause and dying of other age related complications.
At the end Lucretia was comfortable, warm, calm, and hydrated at the vet clinic; after determining there was nothing he could do for her, the vet gassed her to death behind closed doors in what we can only assume (and hope) was a humane way. We buried her under a tamarillo bush.
Interestingly, if you look at the background of the above photo you may notice Plantago (plantain - but I'll call it Plantago to avoid common-name confusion with Musa species) under Lucretia's feet. I'm about 98% sure its Plantago lancelota - I haven't formally keyed it out.
Our chickens have destroyed all forms of greenery within their domain except the Plantago which they will not touch (we supplement them daily with plenty of additional greens from the gardens and property).
As a result Plantago is spreading rapidly throughout their enclosure - the chickens are structuring the plant-community composition within the pen. In terms of food-web theory this would be considered top-down control on plant-community composition by the chickens.
The chickens are inadvertently selecting for the Plantago (more precisely the mechanism and ultimately alleles responsible for its unpalatability). Should a mutant Plantago arise that lacks this chemical and/or structural defense against chicken-browse (and should the chickens decide to sample it) it will be toast. Whatever alleles are responsible for the characters making Plantago inedible are probaly undergoing stabilising selection. At one end alleles resulting in a reduction of unpalatability would be purified by the chickens - those plants (allele sacks) wouldn't live long enough to pass on said alleles to the next generation. At the other end alleles resulting in more extreme (but unnecessary) amounts of defence might involve a resource-allocation based trade-off that would leave those plants at a disadvantage with their con-specifics.
If some other plant species equally unpalatable to chickens disperses into the pen its frequency may also continue to increase - but that would be determined by its ability to effectively compete with the established Plantago for resources (light, nutrients, space).
Over a much, much longer time period (assuming the chickens continued their brand of top-down control) other cool interactions could occur: Forms of unrelated plants resembling Plantago might arise (mimicry). Chickens with a taste for/ability to utilise Plantago might also arise (if we added a rooster or two), giving them an advantage over chickens with more restricted diets.
At the end Lucretia was comfortable, warm, calm, and hydrated at the vet clinic; after determining there was nothing he could do for her, the vet gassed her to death behind closed doors in what we can only assume (and hope) was a humane way. We buried her under a tamarillo bush.
Interestingly, if you look at the background of the above photo you may notice Plantago (plantain - but I'll call it Plantago to avoid common-name confusion with Musa species) under Lucretia's feet. I'm about 98% sure its Plantago lancelota - I haven't formally keyed it out.
Our chickens have destroyed all forms of greenery within their domain except the Plantago which they will not touch (we supplement them daily with plenty of additional greens from the gardens and property).
As a result Plantago is spreading rapidly throughout their enclosure - the chickens are structuring the plant-community composition within the pen. In terms of food-web theory this would be considered top-down control on plant-community composition by the chickens.
The chickens are inadvertently selecting for the Plantago (more precisely the mechanism and ultimately alleles responsible for its unpalatability). Should a mutant Plantago arise that lacks this chemical and/or structural defense against chicken-browse (and should the chickens decide to sample it) it will be toast. Whatever alleles are responsible for the characters making Plantago inedible are probaly undergoing stabilising selection. At one end alleles resulting in a reduction of unpalatability would be purified by the chickens - those plants (allele sacks) wouldn't live long enough to pass on said alleles to the next generation. At the other end alleles resulting in more extreme (but unnecessary) amounts of defence might involve a resource-allocation based trade-off that would leave those plants at a disadvantage with their con-specifics.
If some other plant species equally unpalatable to chickens disperses into the pen its frequency may also continue to increase - but that would be determined by its ability to effectively compete with the established Plantago for resources (light, nutrients, space).
Over a much, much longer time period (assuming the chickens continued their brand of top-down control) other cool interactions could occur: Forms of unrelated plants resembling Plantago might arise (mimicry). Chickens with a taste for/ability to utilise Plantago might also arise (if we added a rooster or two), giving them an advantage over chickens with more restricted diets.
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