I was just talking to a friend, who reported his conversation with a friend of his who was an evolution-doubter. The e-d said that evolution couldn't explain "the tear duct".
I've never heard this one before.
Have any of you? What is supposed to be the problem with the evolution of the tear duct?
-- ---Tom S. the failure to nail currant jelly to a wall is not due to the nail; it is due to the currant jelly. Theodore Roosevelt, Letter to William Thayer, 1915 July 2
On Nov 4, 10:29 am, TomS <TomS_mem...@newsguy.com> wrote:
> I was just talking to a friend, who reported his conversation with > a friend of his who was an evolution-doubter. The e-d said that evolution > couldn't explain "the tear duct".
> I've never heard this one before.
> Have any of you? What is supposed to be the problem with the evolution > of the tear duct?
<sarcasm> Which evolved first, tear ducts or the tears? If the former, they would have conferred no advantage; if the latter, tears would have built up until the creature's head exploded. </sarcasm>
On 4 Nov 2009 07:29:48 -0800, TomS <TomS_mem...@newsguy.com> wrote:
>I was just talking to a friend, who reported his conversation with >a friend of his who was an evolution-doubter. The e-d said that evolution >couldn't explain "the tear duct".
>I've never heard this one before.
>Have any of you? What is supposed to be the problem with the evolution >of the tear duct?
Tear ducts are found in pretty much all tetrapods. But there really is a question of what they are supposed to do. Carrying off excess tears is not much use -- there is no problem in just having the fluid run out of the eye. And there is no particular value in shunting it into the nasal cavity. So the problem is why it should be there at all.
Willem Hilllenius, the chair of the Biology department at the College at Charleston, is interested in the Harderian gland in amphibians. This is a specialized gland in the eye orbit of many tetrapods and Hillenius (with Susan Rehorek of Slippery Rock University) speculates that its secretions might be closely connected with the vomeronasal (Jacobson's) organ, a sensory structure in the nasal passages. They have a paper in J. Herpetology
WJ Hillenius, LK Watrobski, and SJ Rehorek Passage of Tear Duct Fluids through the Nasal Cavity of Frogs J. Herpetology 35(4):701-704 ( 2001) http://www.jstor.org/pss/1565918
showing that the lacrimal duct transmits fluid from the Harderian gland to the vomeronasal organ. Thus the secretions of the gland could be used to bind to and carry scents, especially pheromones, picked up from the air (or water in the case of amphibian animals) to the sensory structure. The Harderian gland - tear duct - vomeronasal organ connection seems to be shared by, for example, frogs and caecilians (among the amphibians) and snakes (among the former Reptiles) and so was probably an important factor in early tetrapod evolution. Using the large, moist exposed surface of the eye to collect scents is probably as effective as the snake habit of flicking out its tongue to capture odors for presentation to the vomeronasal organ.
On Wed, 4 Nov 2009 08:33:12 -0800 (PST), Mitchell Coffey
<m.cof...@starpower.net> wrote: > On Nov 4, 10:29 am, TomS <TomS_mem...@newsguy.com> wrote: > > I was just talking to a friend, who reported his conversation with > > a friend of his who was an evolution-doubter. The e-d said that evolution > > couldn't explain "the tear duct".
> > I've never heard this one before.
> > Have any of you? What is supposed to be the problem with the evolution > > of the tear duct? > <sarcasm> > Which evolved first, tear ducts or the tears? If the former, they > would have conferred no advantage; if the latter, tears would have > built up until the creature's head exploded. > </sarcasm>
Yes, but it's *STILL* salt water!
-- http://desertphile.org Desertphile's Desert Soliloquy. WARNING: view with plenty of water "Why aren't resurrections from the dead noteworthy?" -- Jim Rutz
>> On Nov 4, 10:29=A0am, TomS <TomS_mem...@newsguy.com> wrote: >> > I was just talking to a friend, who reported his conversation with >> > a friend of his who was an evolution-doubter. The e-d said that evolu= >tion >> > couldn't explain "the tear duct".
>> > I've never heard this one before.
>> > Have any of you? What is supposed to be the problem with the evolutio= >n >> > of the tear duct? >=20 >> <sarcasm> >> Which evolved first, tear ducts or the tears? If the former, they >> would have conferred no advantage; if the latter, tears would have >> built up until the creature's head exploded. >> </sarcasm> >=20 >Yes, but it's *STILL* salt water!
I like that.
I'm tempted to bring up something like that whenever a creationist speaks about the supposed impossibility of a particular evolutionary transition - let's say between the jaw-bone of a reptile and the middle-ear bone of a mammal: "It's still a bone."
-- ---Tom S. the failure to nail currant jelly to a wall is not due to the nail; it is due to the currant jelly. Theodore Roosevelt, Letter to William Thayer, 1915 July 2
>On 4 Nov 2009 07:29:48 -0800, TomS <TomS_mem...@newsguy.com> wrote:
>>I was just talking to a friend, who reported his conversation with >>a friend of his who was an evolution-doubter. The e-d said that evolution >>couldn't explain "the tear duct".
>>I've never heard this one before.
>>Have any of you? What is supposed to be the problem with the evolution >>of the tear duct?
>Tear ducts are found in pretty much all tetrapods. But there really >is a question of what they are supposed to do. Carrying off excess >tears is not much use -- there is no problem in just having the fluid >run out of the eye. And there is no particular value in shunting it >into the nasal cavity. So the problem is why it should be there at >all.
>Willem Hilllenius, the chair of the Biology department at the College >at Charleston, is interested in the Harderian gland in amphibians. >This is a specialized gland in the eye orbit of many tetrapods and >Hillenius (with Susan Rehorek of Slippery Rock University) speculates >that its secretions might be closely connected with the vomeronasal >(Jacobson's) organ, a sensory structure in the nasal passages. They >have a paper in J. Herpetology
> WJ Hillenius, LK Watrobski, and SJ Rehorek > Passage of Tear Duct Fluids through the Nasal > Cavity of Frogs > J. Herpetology 35(4):701-704 ( 2001) > http://www.jstor.org/pss/1565918
>showing that the lacrimal duct transmits fluid from the Harderian >gland to the vomeronasal organ. Thus the secretions of the gland could >be used to bind to and carry scents, especially pheromones, picked up >from the air (or water in the case of amphibian animals) to the >sensory structure. The Harderian gland - tear duct - vomeronasal >organ connection seems to be shared by, for example, frogs and >caecilians (among the amphibians) and snakes (among the former >Reptiles) and so was probably an important factor in early tetrapod >evolution. Using the large, moist exposed surface of the eye to >collect scents is probably as effective as the snake habit of flicking >out its tongue to capture odors for presentation to the vomeronasal >organ.
Thanks. I'll pass this on to my friend.
-- ---Tom S. the failure to nail currant jelly to a wall is not due to the nail; it is due to the currant jelly. Theodore Roosevelt, Letter to William Thayer, 1915 July 2
>On 4 Nov 2009 07:29:48 -0800, TomS <TomS_mem...@newsguy.com> wrote:
>>I was just talking to a friend, who reported his conversation with >>a friend of his who was an evolution-doubter. The e-d said that evolution >>couldn't explain "the tear duct".
>>I've never heard this one before.
>>Have any of you? What is supposed to be the problem with the evolution >>of the tear duct?
>Tear ducts are found in pretty much all tetrapods. But there really >is a question of what they are supposed to do. Carrying off excess >tears is not much use -- there is no problem in just having the fluid >run out of the eye. And there is no particular value in shunting it >into the nasal cavity. So the problem is why it should be there at >all.
>Willem Hilllenius, the chair of the Biology department at the College >at Charleston, is interested in the Harderian gland in amphibians. >This is a specialized gland in the eye orbit of many tetrapods and >Hillenius (with Susan Rehorek of Slippery Rock University) speculates >that its secretions might be closely connected with the vomeronasal >(Jacobson's) organ, a sensory structure in the nasal passages. They >have a paper in J. Herpetology
> WJ Hillenius, LK Watrobski, and SJ Rehorek > Passage of Tear Duct Fluids through the Nasal > Cavity of Frogs > J. Herpetology 35(4):701-704 ( 2001) > http://www.jstor.org/pss/1565918
>showing that the lacrimal duct transmits fluid from the Harderian >gland to the vomeronasal organ. Thus the secretions of the gland could >be used to bind to and carry scents, especially pheromones, picked up >from the air (or water in the case of amphibian animals) to the >sensory structure. The Harderian gland - tear duct - vomeronasal >organ connection seems to be shared by, for example, frogs and >caecilians (among the amphibians) and snakes (among the former >Reptiles) and so was probably an important factor in early tetrapod >evolution. Using the large, moist exposed surface of the eye to >collect scents is probably as effective as the snake habit of flicking >out its tongue to capture odors for presentation to the vomeronasal >organ.
Thanks. I'll pass this on to my friend.
-- ---Tom S. the failure to nail currant jelly to a wall is not due to the nail; it is due to the currant jelly. Theodore Roosevelt, Letter to William Thayer, 1915 July 2
>On 4 Nov 2009 07:29:48 -0800, TomS <TomS_mem...@newsguy.com> wrote:
>>I was just talking to a friend, who reported his conversation with >>a friend of his who was an evolution-doubter. The e-d said that evolution >>couldn't explain "the tear duct".
>>I've never heard this one before.
>>Have any of you? What is supposed to be the problem with the evolution >>of the tear duct?
>Tear ducts are found in pretty much all tetrapods. But there really >is a question of what they are supposed to do. Carrying off excess >tears is not much use -- there is no problem in just having the fluid >run out of the eye. And there is no particular value in shunting it >into the nasal cavity. So the problem is why it should be there at >all.
>Willem Hilllenius, the chair of the Biology department at the College >at Charleston, is interested in the Harderian gland in amphibians. >This is a specialized gland in the eye orbit of many tetrapods and >Hillenius (with Susan Rehorek of Slippery Rock University) speculates >that its secretions might be closely connected with the vomeronasal >(Jacobson's) organ, a sensory structure in the nasal passages. They >have a paper in J. Herpetology
> WJ Hillenius, LK Watrobski, and SJ Rehorek > Passage of Tear Duct Fluids through the Nasal > Cavity of Frogs > J. Herpetology 35(4):701-704 ( 2001) > http://www.jstor.org/pss/1565918
>showing that the lacrimal duct transmits fluid from the Harderian >gland to the vomeronasal organ. Thus the secretions of the gland could >be used to bind to and carry scents, especially pheromones, picked up >from the air (or water in the case of amphibian animals) to the >sensory structure. The Harderian gland - tear duct - vomeronasal >organ connection seems to be shared by, for example, frogs and >caecilians (among the amphibians) and snakes (among the former >Reptiles) and so was probably an important factor in early tetrapod >evolution. Using the large, moist exposed surface of the eye to >collect scents is probably as effective as the snake habit of flicking >out its tongue to capture odors for presentation to the vomeronasal >organ.
Thanks. I'll pass this on to my friend.
-- ---Tom S. the failure to nail currant jelly to a wall is not due to the nail; it is due to the currant jelly. Theodore Roosevelt, Letter to William Thayer, 1915 July 2
On 4 Nov 2009 07:29:48 -0800, the following appeared in talk.origins, posted by TomS <TomS_mem...@newsguy.com>:
>I was just talking to a friend, who reported his conversation with >a friend of his who was an evolution-doubter. The e-d said that evolution >couldn't explain "the tear duct".
>I've never heard this one before.
>Have any of you? What is supposed to be the problem with the evolution >of the tear duct?
There is no problem; creationists tend to grasp at illusory straws. --
Bob C.
"Evidence confirming an observation is evidence that the observation is wrong." - McNameless
Mitchell Coffey <m.cof...@starpower.net> wrote: > On Nov 4, 10:29 am, TomS <TomS_mem...@newsguy.com> wrote: > > I was just talking to a friend, who reported his conversation with > > a friend of his who was an evolution-doubter. The e-d said that evolution > > couldn't explain "the tear duct".
> > I've never heard this one before.
> > Have any of you? What is supposed to be the problem with the evolution > > of the tear duct?
> <sarcasm> > Which evolved first, tear ducts or the tears? If the former, they > would have conferred no advantage; if the latter, tears would have > built up until the creature's head exploded. > </sarcasm>
John Wilkins <j...@wilkins.id.au> wrote: > In article > <a9f7c7a6-4c79-462a-b8f8-0d11c6dcf...@m26g2000yqb.googlegroups.com>, > Mitchell Coffey <m.cof...@starpower.net> wrote:
> > On Nov 4, 10:29 am, TomS <TomS_mem...@newsguy.com> wrote: > > > I was just talking to a friend, who reported his conversation with > > > a friend of his who was an evolution-doubter. The e-d said that evolution > > > couldn't explain "the tear duct".
> > > I've never heard this one before.
> > > Have any of you? What is supposed to be the problem with the evolution > > > of the tear duct?
> > <sarcasm> > > Which evolved first, tear ducts or the tears? If the former, they > > would have conferred no advantage; if the latter, tears would have > > built up until the creature's head exploded. > > </sarcasm>
> In article > <a9f7c7a6-4c79-462a-b8f8-0d11c6dcf...@m26g2000yqb.googlegroups.com>,
> Mitchell Coffey <m.cof...@starpower.net> wrote: > > On Nov 4, 10:29 am, TomS <TomS_mem...@newsguy.com> wrote: > > > I was just talking to a friend, who reported his conversation with > > > a friend of his who was an evolution-doubter. The e-d said that evolution > > > couldn't explain "the tear duct".
> > > I've never heard this one before.
> > > Have any of you? What is supposed to be the problem with the evolution > > > of the tear duct?
> > <sarcasm> > > Which evolved first, tear ducts or the tears? If the former, they > > would have conferred no advantage; if the latter, tears would have > > built up until the creature's head exploded. > > </sarcasm>
On Nov 4, 1:04 pm, r norman <r_s_nor...@comcast.net> wrote:
> The Harderian gland - tear duct - vomeronasal > organ connection seems to be shared by, for example, frogs and > caecilians (among the amphibians) and snakes (among the former > Reptiles)
Snakes are former reptiles? What are they now if they're no longer reptiles? Although the class Reptiles is not a good classification since snakes and lizards share a more recent common ancestor with birds than they do with turtles.
On Thu, 5 Nov 2009 05:48:30 -0800 (PST), Ken Denny <k...@kendenny.com> wrote:
>On Nov 4, 1:04 pm, r norman <r_s_nor...@comcast.net> wrote: >> The Harderian gland - tear duct - vomeronasal >> organ connection seems to be shared by, for example, frogs and >> caecilians (among the amphibians) and snakes (among the former >> Reptiles)
>Snakes are former reptiles? What are they now if they're no longer >reptiles? >Although the class Reptiles is not a good classification since snakes >and lizards share a more recent common ancestor with birds than they >do with turtles.
That is what I meant. The "new reptiles" include birds and the "old reptiles", the ones that people think of as reptiles, are extinct -- the word, that is, not the animals.
|
