Bromeliads - Pineapples
 

Hey guys,

I'm a college student and I'm trying to dig up information about the
evolutionary advantage of bromelain in pineapples. Could anyone give me a
few pointers or lead me in the right direction?

Thanks!

Bromeliads - Pineapples
 

In article ,
Lambert wrote:

I'm a college student and I'm trying to dig up information about the
evolutionary advantage of bromelain in pineapples. Could anyone give me a
few pointers or lead me in the right direction?

Do an experiment. Buy a whole fresh pineapple. Peel and eat. Reflect
that domestic pineapples have been highly selected for palatability.

Note that cooked (e.g. canned) pineapple does not have the same effect.

Bromeliads - Pineapples
 

I know about the effects of bromelin on polypeptide chains and how it
hydrolizes proteins. Also, the canning process denatures the enzymes via
heat. Hence you don't get the tingling sensation on your tongue (the
pineapple is actually catalysing proteins on your tongue.)

I'm just wondering about why the pineapple and other fruits (papayas,
pawpaws) have evolved to have bromelin enzymes. What exactly is the
particular survival advantage of having such a trait?

"Beverly Erlebacher" wrote in message
. ..
In article ,
Lambert wrote:

I'm a college student and I'm trying to dig up information about the
evolutionary advantage of bromelain in pineapples. Could anyone give me a
few pointers or lead me in the right direction?

Do an experiment. Buy a whole fresh pineapple. Peel and eat. Reflect
that domestic pineapples have been highly selected for palatability.

Note that cooked (e.g. canned) pineapple does not have the same effect.

Bromeliads - Pineapples
 

Lambert schreef
I know about the effects of bromelin on polypeptide chains and how it
hydrolizes proteins. Also, the canning process denatures the enzymes via
heat. Hence you don't get the tingling sensation on your tongue (the
pineapple is actually catalysing proteins on your tongue.)

I'm just wondering about why the pineapple and other fruits (papayas,
pawpaws) have evolved to have bromelin enzymes. What exactly is the
particular survival advantage of having such a trait?

+ + +

One of the avenues to explore is the direct one:
these enzymes are in the fruits
the fruits are eaten, and hopefully the seeds are spread
the plants that has the fruits that are preferred by those animals that
spread the fruits the furthest or to the most suitable locations will
survive best
etc

Another is the systematic approach
in what plant groups do these enzyms occur?
do these plant groups have similar enzyms used for something else?
etc
PvR

Bromeliads - Pineapples
 

I've done some rough research and all I can come up with is that the enzyme
may have something to do with the plant's method to acquire nutrients. The
crown at the top of the pineapple collects decomposing material and absorbs
nutrients this way.

I thought about the enzymes being appealing for eating etc. but Bromelin
hydrolizes proteins and would be generally uncomfortable for an animal to
eat (speculation)? Certainly when humans eat pineapples their tongues can
feel itchy/raw/red etc...


"P van Rijckevorsel" wrote in message
.. .
Lambert schreef
I know about the effects of bromelin on polypeptide chains and how it
hydrolizes proteins. Also, the canning process denatures the enzymes via
heat. Hence you don't get the tingling sensation on your tongue (the
pineapple is actually catalysing proteins on your tongue.)

I'm just wondering about why the pineapple and other fruits (papayas,
pawpaws) have evolved to have bromelin enzymes. What exactly is the
particular survival advantage of having such a trait?

+ + +

One of the avenues to explore is the direct one:
these enzymes are in the fruits
the fruits are eaten, and hopefully the seeds are spread
the plants that has the fruits that are preferred by those animals that
spread the fruits the furthest or to the most suitable locations will
survive best
etc

Another is the systematic approach
in what plant groups do these enzyms occur?
do these plant groups have similar enzyms used for something else?
etc
PvR

Bromeliads - Pineapples
 

From: "P van Rijckevorsel"

I'm just wondering about why the pineapple and other fruits (papayas,
pawpaws) have evolved to have bromelin enzymes. What exactly is the
particular survival advantage of having such a trait?

+ + +

One of the avenues to explore is the direct one:
these enzymes are in the fruits
the fruits are eaten, and hopefully the seeds are spread
the plants that has the fruits that are preferred by those animals that
spread the fruits the furthest or to the most suitable locations will
survive best
etc

Another is the systematic approach
in what plant groups do these enzyms occur?
do these plant groups have similar enzyms used for something else?
etc

I think the question sounds like, "why would a plant develop an enzyme that
digests a potential seed distributor?" Maybe the seeds are distributed by a
some organism with a salivary component that neutralizes the bromelin, and this
is a way to get specificity for a distributor.

Sean



--
Visit my photolog page; http://members.aol.com/grommit383/myhomepage
Last updated 08-04-02 with 15 pictures of the Aztec Ruins.
Address mungled. To email, please spite my face.

Bromeliads - Pineapples
 

This is assuming that a diet consists of pineaple only
PvR

Lambert schreef
I've done some rough research and all I can come up with is that the
enzyme may have something to do with the plant's method to acquire
nutrients. The crown at the top of the pineapple collects decomposing
material and absorbs nutrients this way.

I thought about the enzymes being appealing for eating etc. but Bromelin
hydrolizes proteins and would be generally uncomfortable for an animal to
eat (speculation)? Certainly when humans eat pineapples their tongues can
feel itchy/raw/red etc...

+ + +

"P van Rijckevorsel" wrote
One of the avenues to explore is the direct one:
these enzymes are in the fruits
the fruits are eaten, and hopefully the seeds are spread
the plants that has the fruits that are preferred by those animals that
spread the fruits the furthest or to the most suitable locations will
survive best
etc

Another is the systematic approach
in what plant groups do these enzyms occur?
do these plant groups have similar enzyms used for something else?
etc
PvR
....
Lambert schreef
I know about the effects of bromelin on polypeptide chains and how it
hydrolizes proteins. Also, the canning process denatures the enzymes via
heat. Hence you don't get the tingling sensation on your tongue (the
pineapple is actually catalysing proteins on your tongue.)

I'm just wondering about why the pineapple and other fruits (papayas,
pawpaws) have evolved to have bromelin enzymes. What exactly is the
particular survival advantage of having such a trait?

Bromeliads - Pineapples
 

Perhaps the "purpose" is insecticidal. Ananas comosus wasn't always seedless
and the enzyme might have functioned as a toxin or repellant to insect larvae that
could have damaged the fruit before the seeds could be dispersed.


"Sean Houtman" wrote in message ...
From: "P van Rijckevorsel"

I'm just wondering about why the pineapple and other fruits (papayas,
pawpaws) have evolved to have bromelin enzymes. What exactly is the
particular survival advantage of having such a trait?

+ + +

One of the avenues to explore is the direct one:
these enzymes are in the fruits
the fruits are eaten, and hopefully the seeds are spread
the plants that has the fruits that are preferred by those animals that
spread the fruits the furthest or to the most suitable locations will
survive best
etc

Another is the systematic approach
in what plant groups do these enzyms occur?
do these plant groups have similar enzyms used for something else?
etc

I think the question sounds like, "why would a plant develop an enzyme that
digests a potential seed distributor?" Maybe the seeds are distributed by a
some organism with a salivary component that neutralizes the bromelin, and this
is a way to get specificity for a distributor.

Sean



--
Visit my photolog page; http://members.aol.com/grommit383/myhomepage
Last updated 08-04-02 with 15 pictures of the Aztec Ruins.
Address mungled. To email, please spite my face.

Bromeliads - Pineapples
 

From: "Jeff Shimonski"

Perhaps the "purpose" is insecticidal. Ananas comosus wasn't always seedless
and the enzyme might have functioned as a toxin or repellant to insect larvae
that
could have damaged the fruit before the seeds could be dispersed.

This also is a reasonable theory. It can easily be tested by examining wild
species of Ananas for fruit predation by insects through various stages of
developement.

Sean



--
Visit my photolog page; http://members.aol.com/grommit383/myhomepage
Last updated 08-04-02 with 15 pictures of the Aztec Ruins.
Address mungled. To email, please spite my face.

Bromeliads - Pineapples
 

From: "Jeff Shimonski"

Perhaps the "purpose" is insecticidal. Ananas comosus wasn't always seedless
and the enzyme might have functioned as a toxin or repellant to insect larvae
that
could have damaged the fruit before the seeds could be dispersed.

This also is a reasonable theory. It can easily be tested by examining wild
species of Ananas for fruit predation by insects through various stages of
developement.

Sean BRBR

This may be a bit off topic, but thought I'd reply to the "Ananas comosus
wasn't always seedless," above. As far as I know, all pineapples are still
completely fertile, and will make plenty of viable seeds IF they are pollenized
by a different cultivar. They are quite self-incompatible, and are grown
commercially in single-variety plantings to force seedlessness.

Bromeliads - Pineapples
 

Definitely some pineapples set seed, and I was incorrect in implying that all
A. comosus were infertile, but you might want to check out some of the literature
by David H. Benzing or perhaps Studies in the Bromeliaceae by Lyman B. Smith,
Contributions from the Reed Herbarium No. 28, 1977 under Ananas pp. 56
"Berry sterile in cultivated forms"


"MMMavocado" wrote in message ...
From: "Jeff Shimonski"

Perhaps the "purpose" is insecticidal. Ananas comosus wasn't always seedless
and the enzyme might have functioned as a toxin or repellant to insect larvae
that
could have damaged the fruit before the seeds could be dispersed.

This also is a reasonable theory. It can easily be tested by examining wild
species of Ananas for fruit predation by insects through various stages of
developement.

Sean BRBR

This may be a bit off topic, but thought I'd reply to the "Ananas comosus
wasn't always seedless," above. As far as I know, all pineapples are still
completely fertile, and will make plenty of viable seeds IF they are pollenized
by a different cultivar. They are quite self-incompatible, and are grown
commercially in single-variety plantings to force seedlessness.

Bromeliads - Pineapples
 

Lambert schreef
I've done some rough research and all I can come up with is that the
enzyme may have something to do with the plant's method to acquire
nutrients. The crown at the top of the pineapple collects decomposing
material and absorbs nutrients this way.

I thought about the enzymes being appealing for eating etc. but Bromelin
hydrolizes proteins and would be generally uncomfortable for an animal to
eat (speculation)? Certainly when humans eat pineapples their tongues can
feel itchy/raw/red etc...

+ + +
A key question is the concentration of such enzymes in the fruits of
the wild progenitors. The present properties of pineapples have been set by
selection in cultivation.
PvR

Bromeliads - Pineapples
 

Also does anyone happen to know the evolutionary history of the pineapple?


"Lambert" wrote in message
u...
Hey guys,

I'm a college student and I'm trying to dig up information about the
evolutionary advantage of bromelain in pineapples. Could anyone give me a
few pointers or lead me in the right direction?

Thanks!

Bromeliads - Pineapples
 

Lambert schreef
Also does anyone happen to know the evolutionary history of the pineapple?

----- Original Message -----
From: P van Rijckevorsel
Sent: Wednesday, April 23, 2003 10:37 AM

+ + +
A key question is the concentration of such enzymes in the fruits of
the wild progenitors. The present properties of pineapples have been set
by selection in cultivation.
PvR

Addendum: the pineapple likely is a hybrid
PvR

Bromeliads - Pineapples
 

You sound like a horticulturist when you dismiss a plant as being a hybrid.
They always confuse cultivars with hybrids.

If Ananas comosus is a hybrid, what are the parent species?

There are more than one species in the genus Ananas, so you have a few to
choose from!




P van Rijckevorsel wrote in message
.. .
Lambert schreef
Also does anyone happen to know the evolutionary history of the
pineapple?

----- Original Message -----
From: P van Rijckevorsel
Sent: Wednesday, April 23, 2003 10:37 AM

+ + +
A key question is the concentration of such enzymes in the fruits of
the wild progenitors. The present properties of pineapples have been set
by selection in cultivation.
PvR

Addendum: the pineapple likely is a hybrid
PvR

Bromeliads - Pineapples
 

You sound like a horticulturist when you dismiss a plant as being a hybrid.
They always confuse cultivars with hybrids.

Hold it! Don't go badmouthing all us horticulturists. You know I can tell the
difference between a hybrid & a cultivar. And a cultivar of a hybrid, for that
matter.
Iris,
Central NY, Zone 5a, Sunset Zone 40
"If we see light at the end of the tunnel, It's the light of the oncoming
train."
Robert Lowell (1917-1977)

Bromeliads - Pineapples
 

Cereoid-XXXXX schreef
You sound like a horticulturist when you dismiss a plant as being a
hybrid. They always confuse cultivars with hybrids.

If Ananas comosus is a hybrid, what are the parent species?

There are more than one species in the genus Ananas, so you have a few to
choose from!

+ + +
This does not seem to require comment except
- "one species" is singular so it should be "There is more than one species"
- if a plant is a hybrid then there should be at least two parents, making
three species already, so "there is more than one species in the genus ..."
is a self-evident and redundant statement
- Ananas has some eight species which does not seem like a big genus to me?
PvR

Bromeliads - Pineapples
 

You didn't answer the question, Rinkytink.

That must be because you have absolutely no idea what you are talking about,
including the proper usage of the English language.

Once again I ask you: If Ananas comosus is a hybrid, what are the parent
species?

Sorry Dude, but there are monotypic genera that contain only a single
species. Ananas isn't one of them.

The word "species" is spelled the same whether you are talking about one or
a million of them.


P van Rijckevorsel wrote in message
.. .
Cereoid-XXXXX schreef
You sound like a horticulturist when you dismiss a plant as being a
hybrid. They always confuse cultivars with hybrids.

If Ananas comosus is a hybrid, what are the parent species?

There are more than one species in the genus Ananas, so you have a few
to
choose from!

+ + +
This does not seem to require comment except
- "one species" is singular so it should be "There is more than one
species"
- if a plant is a hybrid then there should be at least two parents, making
three species already, so "there is more than one species in the genus
...."
is a self-evident and redundant statement
- Ananas has some eight species which does not seem like a big genus to
me?
PvR

Bromeliads - Pineapples
 

Did you do a google search for websites on the pineapple?

There are several out there that will answer all your questions.

It seems that college students keep getting lazier and lazier with every
semester.


Lambert wrote in message
u...
Also does anyone happen to know the evolutionary history of the pineapple?


"Lambert" wrote in message
u...
Hey guys,

I'm a college student and I'm trying to dig up information about the
evolutionary advantage of bromelain in pineapples. Could anyone give me
a
few pointers or lead me in the right direction?

Thanks!

Bromeliads - Pineapples
 

Cereoid-XXXXX schreef
You didn't answer the question, Rinkytink.

+ + +
Some people should do their own homework
+ + +

[...] but there are monotypic genera that contain only a single species.

+ + +
Actually, all monotypic genera contain only a single species.
+ + +

I am pretty sure that Ananas isn't one of them.

+ + +
I pointed out that Ananas has some eight species, so I am not sure what you
are not sure of. Last message you claimed that Ananas was so big that it had
you confused.
+ + +

The word "species" is spelled the same whether you are talking about one
or
a million of them.

+ + +
However the word one is a number, and it goes with verbs in the singular
PvR
+ + +

Bromeliads - Pineapples
 

You remain the undefeated troll of this group, Rinkytink.

Although you had previously said that Ananas comosus is a species of hybrid
origin, you repeatedly fail to back up your claim with any facts or any
possible species that may be its parents. You don't even provide a listing
of the accepted species in the genus.

I maintain that your statement was a false one and that you just don't have
the balls to admit you made a mistake.

Your being an evasive smartass doesn't get you off the hook, dude.

Try practicing what you preach and do your own homework.


P van Rijckevorsel wrote in message
.. .
Cereoid-XXXXX schreef
You didn't answer the question, Rinkytink.

+ + +
Some people should do their own homework
+ + +

[...] but there are monotypic genera that contain only a single species.

+ + +
Actually, all monotypic genera contain only a single species.
+ + +

I am pretty sure that Ananas isn't one of them.

+ + +
I pointed out that Ananas has some eight species, so I am not sure what
you
are not sure of. Last message you claimed that Ananas was so big that it
had
you confused.
+ + +

The word "species" is spelled the same whether you are talking about one
or
a million of them.

+ + +
However the word one is a number, and it goes with verbs in the singular
PvR
+ + +

Bromeliads - Pineapples
 

This is a very simple matter.

In my book it says that the pineapple is a hybrid. I am convinced it is a
very good book, but if there are two areas with a confused taxonomy then it
is monocots and cultivated plants. The pine-apple is both.

I have no need to establish anything. In response to a question about why
pine-apples have the properties they do have I pointed out that these
properties are the result of selection in cultivation and that the
pine-apple is regarded as a hybrid.

Anybody who wants more can do his own homework.
PvR

Bromeliads - Pineapples
 

You have established that you are really full of BS, Rinkytink. You also
have all the properties of a troll.

You neither give the name of the book (if it even exists) nor the purported
parentage of Ananas comosus. Obviously, you are not able to give any basis
in reality to support your fabrication and your assertion has absolutely no
merit at all in truth. You haven't done your own homework. You are just
pontificating nonsense again.

Selection of cultivars does not need to be from interspecific hybrids.


P van Rijckevorsel wrote in message
.. .
This is a very simple matter.

In my book it says that the pineapple is a hybrid. I am convinced it is a
very good book, but if there are two areas with a confused taxonomy then
it
is monocots and cultivated plants. The pine-apple is both.

I have no need to establish anything. In response to a question about why
pine-apples have the properties they do have I pointed out that these
properties are the result of selection in cultivation and that the
pine-apple is regarded as a hybrid.

Anybody who wants more can do his own homework.
PvR

Bromeliads - Pineapples
 

Cereoid-XXXXX schreef
You neither give the name of the book (if it even exists)

+ + +
If you are in such a need of a book, maybe you should buy one every so
often. It can be very educational.
+ + +

Selection of cultivars does not need to be from interspecific hybrids.

+ + +
Maybe you should consult the archives of the list. This was covered pretty
extensively a while back
PvR

Bromeliads - Pineapples
 

From: "P van Rijckevorsel"


Cereoid-XXXXX schreef
You neither give the name of the book (if it even exists)

+ + +
If you are in such a need of a book, maybe you should buy one every so
often. It can be very educational.
+ + +


Now, Cereoid is a cactus freak, and since pineapples are spiny, they must be
cacti, so he knows more than you do!

Sean



--
Visit my photolog page; http://members.aol.com/grommit383/myhomepage
Last updated 08-04-02 with 15 pictures of the Aztec Ruins.
Address mungled. To email, please spite my face.

Bromeliads - Pineapples
 

Sean Houtman schreef
Now, Cereoid is a cactus freak, and since pineapples are spiny, they must
be cacti, so he knows more than you do!

Sean

+ + +
That might true if the issue at stake was the horticulture of pineapples
(Cereoid having so many friends in horticultural circles)
PvR

Bromeliads - Pineapples
 

There are quite a few xerophytic succulent bromeliads, especially in the
genera Hechtia, Dyckia, Deuterocohnia (including Abromeitiella), etc.

If there is any actual documentation proving that Ananas comosus is of
hybrid origin, I would like to see it. However, that does not appear to be
the case at all. Rinkytink is just being his usual evasive obnoxious self. I
have seen much of the bromeliad literature and no such article or book
exists. I gave him a chance to redeem himself by asking to cite his actual
references but he isn't up to the challenge, as usual. One is forced to
conclude his wild claim is fantasy.


Sean Houtman wrote in message
...
From: "P van Rijckevorsel"


Cereoid-XXXXX schreef
You neither give the name of the book (if it even exists)

+ + +
If you are in such a need of a book, maybe you should buy one every so
often. It can be very educational.
+ + +


Now, Cereoid is a cactus freak, and since pineapples are spiny, they must
be
cacti, so he knows more than you do!

Sean