When you poke a Euglena[1] with a pin while looking at it under a microscope, its sensors detect an intrusion and immediately start flapping the flagella (the thing it uses for locomotion, analogous to a leg) to get out of the way. That's a super-simple nervous system. Many plants do this as well, using a slow production of chemicals which move branches and leaves.
As you get more advanced, going up the biological totem pole, every creature uses that exact same sensor => action mechanism. Pain is the brain's complex interpretation of the pin prick, and an animal attempting to remove itself from the source of the pain is the same as activating the flagella.
My brain has mirror neurons which make me literally feel your suffering as you experience it, which is why humans are so against "pain" and "suffering". It's also why I personally will never injure another human, or even another animal, purposefully.
Is it more "wrong" in any scientific way to injure a human instead of a dolphin or a bear or a chimp or a plant -- or even to break a window? Absolutely not. This is why science should never be used to prove or disprove human "morals" and morals should never dictate the functions of science.
I admit that I had never heard of the Euglena before, although the same article seems to be suggesting that the very characteristics you have pointed out cause some scientists to want to classify it as an animal. The suggestion being that the hallmark of "animality" is the ability to feel things.
In any case, I do not (intentionally) consume a great deal of Euglena, so I will content myself with pointing out that grains, vegetables, and fruit upon which I rely to replace the inhumane bounty of factory farming never bled, farted or blinked, and never will. I'm not trying to sound like a holier-than-thou vegetarian here; I'm not, and I have always made a point of not judging how others approach this issue. But if you're going to deconstruct my reasoning, the use of a red herring is discouraged.
As to your last question, the answer is "yes", and the case has been made in the book I mentioned far better than I can here. If you equate breaking a window with killing a dolphin, bear, or chimp, well, that speaks volumes.
When you poke a Euglena[1] with a pin while looking at it under a microscope, its sensors detect an intrusion and immediately start flapping the flagella (the thing it uses for locomotion, analogous to a leg) to get out of the way. That's a super-simple nervous system. Many plants do this as well, using a slow production of chemicals which move branches and leaves.
As you get more advanced, going up the biological totem pole, every creature uses that exact same sensor => action mechanism. Pain is the brain's complex interpretation of the pin prick, and an animal attempting to remove itself from the source of the pain is the same as activating the flagella.
My brain has mirror neurons which make me literally feel your suffering as you experience it, which is why humans are so against "pain" and "suffering". It's also why I personally will never injure another human, or even another animal, purposefully.
Is it more "wrong" in any scientific way to injure a human instead of a dolphin or a bear or a chimp or a plant -- or even to break a window? Absolutely not. This is why science should never be used to prove or disprove human "morals" and morals should never dictate the functions of science.
[1] http://en.wikipedia.org/wiki/Euglena