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07 Jan 2015, 3:25 am
07 Jan 2015, 8:35 pm
07 Jan 2015, 8:46 pm
07 Jan 2015, 10:17 pm
07 Jan 2015, 11:48 pm
08 Jan 2015, 12:08 am
08 Jan 2015, 9:40 am
naturalplastic wrote:
ooOoOoOAnaOoOoOoo wrote:
According to Darwin's Theory of Evolution, there's a reason why animals evolved luxuriant fur, it doesn't just magically happen, it isn't left to chance.
That's what I said. It did not happen by magic. Animals with luxuriant fur evolved it to keep warm in cold environments.
The fact the functional fur also happens to be asthetically pleasing to humans IS an accident. That does not contradict Darwin.
We like to look at peacock feathers. But humans don't have feathers. We like to smell flowers but we dont give off flower like scents ourselves.
Just because something has a quality, or even the trait itsself does not mean it evolved to have that quality, or even the trait itsself exists because it was selected for. It could be a by product of other things being selected for.
Modern humans have chins. But there is no evidence that chins were selected for. Chins were a by product of of the fact that our teeth shrank faster than our jaws shrank-leaving excess jaw bone thrusting forward.
Perhaps but I would need proof that luxuriant fur is actually warmer and more practical than non luxuriant fur to be sure..
08 Jan 2015, 10:53 am
ooOoOoOAnaOoOoOoo wrote:
naturalplastic wrote:
ooOoOoOAnaOoOoOoo wrote:
According to Darwin's Theory of Evolution, there's a reason why animals evolved luxuriant fur, it doesn't just magically happen, it isn't left to chance.
That's what I said. It did not happen by magic. Animals with luxuriant fur evolved it to keep warm in cold environments.
The fact the functional fur also happens to be asthetically pleasing to humans IS an accident. That does not contradict Darwin.
We like to look at peacock feathers. But humans don't have feathers. We like to smell flowers but we dont give off flower like scents ourselves.
Just because something has a quality, or even the trait itsself does not mean it evolved to have that quality, or even the trait itsself exists because it was selected for. It could be a by product of other things being selected for.
Modern humans have chins. But there is no evidence that chins were selected for. Chins were a by product of of the fact that our teeth shrank faster than our jaws shrank-leaving excess jaw bone thrusting forward.
Perhaps but I would need proof that luxuriant fur is actually warmer and more practical than non luxuriant fur to be sure..
What is called "luxuriant" is fur that prevents heat loss.
http://www.osa.org/en-us/about_osa/newsroom/news_releases/2014/fur_and_feathers_keep_animals_warm_by_scattering_l/
Quote:
Simonis and her team tackled the question by re-examining two of the different ways heat can travel: radiation, which transfers thermal energy through electromagnetic waves, and conduction, which transfers thermal energy through the vibrations of neighboring atoms and molecules. Most people assume that fur and feathers keep animals warm primarily by trapping a layer of air that slows thermal conduction, says Simonis. But she and her colleagues suspected that radiation might play a bigger role.
The scientists performed some initial calculations that showed heat loss between two bodies separated by air would be dominated by radiation, not conduction. To further explore the radiative heat loss the team created a simple computer model consisting of a hot and a cold thermostat that roughly simulated an animal’s warm body and the outside, colder environment. The two thermostats were separated by an empty space into which were added “radiative shields” that could mimic individual hairs in a fur coat.
In one version of the model, the researchers incorporated so-called black-body shields, which absorb all of the radiation that strikes them. In a second version, opaque grey-body shields were used. “A grey body has some transmission and reflection as well,” Simonis explains.
Simonis and her colleagues found that as the reflectivity of the radiative shields increased, the rate of heat transfer between the hot and cold thermostat was dramatically reduced. Adding more shields also dramatically reduced the energy loss. All together, the model suggests that the repeated backscattering of infrared light between radiative shields, like individual hairs and barbed feathers, could be the primary mechanism for the thermal insulation properties of fur and feathers.
The scientists performed some initial calculations that showed heat loss between two bodies separated by air would be dominated by radiation, not conduction. To further explore the radiative heat loss the team created a simple computer model consisting of a hot and a cold thermostat that roughly simulated an animal’s warm body and the outside, colder environment. The two thermostats were separated by an empty space into which were added “radiative shields” that could mimic individual hairs in a fur coat.
In one version of the model, the researchers incorporated so-called black-body shields, which absorb all of the radiation that strikes them. In a second version, opaque grey-body shields were used. “A grey body has some transmission and reflection as well,” Simonis explains.
Simonis and her colleagues found that as the reflectivity of the radiative shields increased, the rate of heat transfer between the hot and cold thermostat was dramatically reduced. Adding more shields also dramatically reduced the energy loss. All together, the model suggests that the repeated backscattering of infrared light between radiative shields, like individual hairs and barbed feathers, could be the primary mechanism for the thermal insulation properties of fur and feathers.
08 Jan 2015, 10:59 am
09 Jan 2015, 1:47 am
Camouflage is also important for predators, as they will be harder to spot by their prey. And it seems most mammals are some shade of brown or grey in temperate climates. Wild cats are also less colorful than many domestic cats, most wild cats have the brown/grey fur with black camo stripes. Cats also use their fur to spread their scent, they have scent glands on their cheeks and on other parts of their body. This way it has also a social function. Picture of cute wildcat with young, they are scentmarking each other:
09 Jan 2015, 1:43 pm
09 Jan 2015, 1:44 pm
trollcatman wrote:
Camouflage is also important for predators, as they will be harder to spot by their prey. And it seems most mammals are some shade of brown or grey in temperate climates. Wild cats are also less colorful than many domestic cats, most wild cats have the brown/grey fur with black camo stripes. Cats also use their fur to spread their scent, they have scent glands on their cheeks and on other parts of their body. This way it has also a social function. Picture of cute wildcat with young, they are scentmarking each other:
I always thought cats with that marking had it because it helped them catch Mackerel. They are known as Mackerel Tabbies.
09 Jan 2015, 1:57 pm
ooOoOoOAnaOoOoOoo wrote:
trollcatman wrote:
Camouflage is also important for predators, as they will be harder to spot by their prey. And it seems most mammals are some shade of brown or grey in temperate climates. Wild cats are also less colorful than many domestic cats, most wild cats have the brown/grey fur with black camo stripes. Cats also use their fur to spread their scent, they have scent glands on their cheeks and on other parts of their body. This way it has also a social function. Picture of cute wildcat with young, they are scentmarking each other:
I always thought cats with that marking had it because it helped them catch Mackerel. They are known as Mackerel Tabbies.
Right.
And penguins are marked the way they are so they can infiltrate parties on Downton Abbey, and chow down on gentlemen dressed in tuxedos!
09 Jan 2015, 2:05 pm
naturalplastic wrote:
ooOoOoOAnaOoOoOoo wrote:
trollcatman wrote:
Camouflage is also important for predators, as they will be harder to spot by their prey. And it seems most mammals are some shade of brown or grey in temperate climates. Wild cats are also less colorful than many domestic cats, most wild cats have the brown/grey fur with black camo stripes. Cats also use their fur to spread their scent, they have scent glands on their cheeks and on other parts of their body. This way it has also a social function. Picture of cute wildcat with young, they are scentmarking each other:
I always thought cats with that marking had it because it helped them catch Mackerel. They are known as Mackerel Tabbies.
Right.
And penguins are marked the way they are so they can infiltrate parties on Downton Abbey, and chow down on gentlemen dressed in tuxedos!
Or, maybe the the men in tuxedos are marked that way due to a subliminal desire to infiltrate top secret Penguin gatherings in order to spy. Penguins secretly plot to take over the world.
