Scientific proof that Plants feel pain
Mu' meneen Brothers and Sisters,
As Salaam Aleikum wa Rahmatullahi wa Barakatuh. (May Allah's
Peace, Mercy and Blessings be upon all of you)
One of our brothers/sisters has asked this question:
Dear brother,
As Salaam Aleikum wa Rahmatullahi wa Barakatuh.
Your forum is doing a tremendous job by educating people about
Islam. May Allah Subhanah reward you the best in this
life and the hereafter.
My question is in reference to an answer you provided to some
brother for his question(1894 why sacrifice animals).
In your answer you rightly said that it has been discovered that
plants too have feelings and that they experience pain. I have a non muslim friend, who is a strict
vegetarian, and resents my non veg eating habits. He
basis his argument only on one thing, that why should we take somebody`s life in order to eat, and when I argue by saying
that he too is doing the same thing by killing plants and eating them, he just
does not seem to believe that plants too feel pain, as they don`t
have a nervous system
I have searched the net extensively and got another qoute from a very learned man(Dr. Zakir Naik www.irf.net), where he
too speaks about the pain felt by plants when cut, but brother, I need proof to
make this friend of mine understand this.
Could you kindly provide me with the same?
I shall be very thankful.
Brother in ISLAM.
(There
may be some grammatical and spelling errors in the above statement. The forum
does not change anything from questions, comments and statements received from
our readers for circulation in confidentiality.)
Answer:
Scientific proof that Plants feel pain
In the
name of Allah, We praise Him, seek His help and ask for His forgiveness.
Whoever Allah guides none can misguide, and whoever He allows to fall astray,
none can guide them aright. We bear witness that there is no one (no idol, no
person, no grave, no prophet, no imam,
no dai,
nobody!) worthy of worship but Allah Alone, and we bear witness that
Muhammad(saws) is His slave-servant and the seal of His Messengers.
Dear
Brother in Islam, please find accompanying article derived from the internet
which prove beyond any doubt that modern science has proved that plants too
have feelings. The article has a lot of
technical terms and data, and may make for exhaustive reading; but various
experiments done in the field of botany has proved that plants do have
feelings.
If your
friend needs more scientific proof to satisfy his doubts whether or not plants
have feelings, we have attached the bibliography for the article presented, and
the name of the book which would more than clarify his doubts.
Whatever
written of Truth and benefit is only due to Allah’s Assistance and Guidance,
and whatever of error is of me. Allah
Alone Knows Best and He is the Only Source of Strength.
Plants Have Feelings Too
Plants are more than just vegetables, they respond to touch, you
can stroke them and they feel it.
An overly simplified way of looking at it is. "All plants have
the power of limited movement, which may be as simple as the plant moving
because it enlarges as it grows. But with carnivorous plant motion can be
extremely fast and striking. Since plants do not have muscle tissue, how do
they do it? There are two main movement mechanisms carnivorous plant use. The
first kind of motion is what Venus Fly Traps use to close their traps. It
involves water pressure. When the trap is activated (by touching trigger hairs
on the leaves), the cells on the inside walls of the trap transfer water to the
outside walls, essentially they become limp. This snaps the leaf closed.
The second kind of motion is powered by cell growth-- -the
tentacles of sundews bend towards prey because the cells on one side of the
tentacles grow. This is similar to the way bimetallic strips are used in
thermostats." Walker, R (1998).
Slightly more complicated and more accurate. "Touching a
trigger hair produces a localised receptor potential
in sensor cells which, if sufficiently large, fires a fast-moving electrical
wave, an action potential, which spreads across the trap lobes. The trap
doesn't move but "remembers" being touched. If a second action
potential is fired, the trap shuts.
The workings of a Venus flytrap." Burrell and Ellison
(1986)
Darwin was fascinated by carnivorous plants, in
particular the Venus flytrap (Dionaea muscipula) and its response touch. He believed that the
way the plant snapped its trap shut indicated the presence of a central nervous
system such as that of an animal but having no equipment or expertise in this
field of study he sought the help of one of the worlds leading medical
physiologists, Dr
John Burdon-Sanderson of the
Over the course of several years (late 1960s - mid 1970s) Burdon-Sanderson
conducted many experiments on the Venus flytrap (Dionaea
muscipula). The first experiment, and possibly the
most remarkably revealing of all, was to attach electrodes to the surface of
the trap lobes in the hope of recording electrical activity. He found that each
time a trigger hair was touched it fired off a wave of electrical activity
almost identical to the nerve impulses, or action potentials, produced by
animal neurons. He then carried out the same experiment on other touch
sensitive plants, such as the movements of the leaves of the Sensitive Plant
(Mimosa pudica) and the curling of the leaves of
sundew plants (Drosera) and always found the same
electrical activity and electrical impulses.
Both Burdon-Sanderson and
Quite a number of universities in the
Due to today’s greater understanding of molecular and
cellular biology it is now clear that animals nervous systems are made up of specialised cells, wired up to communicate through synapses
via nerve fibres and networks of neurons. And in
contrast the action potentials of plants travel through ordinary cells by means
of microscopic membrane pores called plasmodesmata,
almost like osmosis. Although animals have a very similar process to plasmodesmata where an action potentials can pass through
pores known as gap junctions, which have the same drawbacks as plasmodesmata.
Plasmodesmata and gap junctions have
their drawbacks, the signals can only be sent down one
route and can only perform one action. For example if you put your hand in a
flame the natural uncontrollable response is for the muscles of the hand and
arm to contract very quickly removing it from the flame, you will have no
control over this action and it will be a second or two before the chemical
trigger wears off and you fully regain control of your arm and hand. Likewise
if a Venus flytrap is touched but does not catch anything (say it has been
pocked buy a pencil) it will close very quickly and it will be several hours
before the chemical trigger wears off and it reopens. Plasmodesmata is also a far
slower process.
Burrell and Ellison (1986) the biochemical calcium trigger in
animals and touch sensitive plants allowing movement "... the main reason
for this flexibility is the chemical versatility of synapses through which
neurons communicate. When an ion potential reaches the end of most nerve fibres, it can't jump the synapse but instead releases
neurotransmitters which fuse across the synapse and trigger an electrical
response in the neuron opposite. Using a variety of different types of
neurotransmitters and neurons, a nervous system can process signals like a
hugely complex telephone exchange, constantly inverting electrical signals into
chemical ones and vice versa, by routing messages to different parts of the
body. A plant cell communicating through plasmodesmata,
by contrast, is much more limited in range and vocabulary: it can only pass
electrical signals down one route and turn on one type of movement. There are
also important similarities. As with neurons, these signals consist of currents
of ions moving to and fro across cell membranes.
Experiments in the 1960s showed that action potentials in the Venus
flytrap, Mimosa and similar touch-sensitive plants are all produced by currents
of the same ions. In each species, a rapid influx of calcium ions into cells
seems to trigger the action potential, and an efflux of potassium and possibly
chloride ions appear to sustain it as it travels from pore to pore. The action
potentials of neurons are produced in a similar way,
they are usually triggered by sodium, not calcium.
Considering its lack of specialised
neurons and synapses, the Venus Flytrap's response to
touch is surprisingly sophisticated. During the late 1960s, Stuart Jacobson, an
insect physiologist
Similar mechanisms seem to operate in Mimosa and the Venus Flytrap's underwater cousin Aidrovanda.
More intriguingly many animal cells also possess sensors that convert
mechanical stimuli such as touch into electrical signals, a prime example being
the "hair" cells of the inner ear's cochlea which produce ionic
currents when their hairs vibrate in response to sound. Coelenterates such as
sea anemones and jellyfish have what is perhaps the closest thing in the animal
kingdom to the neural system of the Venus flytrap, a nerve net where touch
sensors, nerves and muscles are all connected without synapses.
But the Venus flytrap and its relatives are no botanical oddballs.
Touch-sensitive movements occur in more than a thousand species, spread across
17 families of flowering plants, and these, too, probably depend on electrical
impulses. Research completed over the past two decades reveals that action
potentials trigger the movements of sundew (Drosera)
carnivorous traps, Mimosa, Biophytum and Neptunia leaves, and Sparmannia, Berberis and Mahonia flowers. All
of which leads to the question, if excitable plants are so widespread, are
"ordinary" plants touch-sensitive too?
Because most plants don't move very much, it is easy to assume they
are not touch-sensitive. But this assumption is wrong, as one American plant
physiologist discovered. Mordechai Jaffe from Athens
University Ohio, started off in the late 1960s by looking at a familiar garden
phenomenon-how pea tendrils coil around a support. Gently stroking a tendril a
few times was enough to trigger the tendril's coiling,
redirecting its growth from a fairly straight habit into rapid bending.
Touch-sensitive tendrils are hardly freaks of nature, and in 1973
this spurred Jaffe to look at how more ordinary plants might react to touching.
Stroking a plant stem for only a few seconds a day, he found, was enough to
stunt the stem growth and widen its girth. The stems began to thicken just 30
minutes after the plants were rubbed. This stunted response helps plants to
withstand the buffeting of the wind.
A milestone in this field, Jaffe's research launched a range of
investigations, particularly into crop plants. A few years ago, for instance,
Norman Biddington and Tony Dearman
at Horticulture Research International, Welleshourne
in Warwickshire, found that greenhouse-grown lettuce and celery seedlings
survived transplantation to the outside much better if they were brushed
lightly with sheets of paper. This is partly because seedlings raised closely
together in seed trays grow tall and "skinny", whereas plants in the
open grow more stunted to withstand the wind. Biddington, Dearman
and others have found that touching plants also helps many of them to fight off
drought, frost or chilling, although nobody understands how.
The degree of response exhibited by plants is quite marked. In
1990, for example, Janet Braam and Ronald Davis of
Touching can also stimulate plants to cut down their water loss by
closing their leaf pores, to delay flower production, and to increase
metabolism and chlorophyll production. There are reports from
Simons, P (1993) Very little was understood about the molecular
level how action potentials spread along the fibres
of neurons, until 1981 when two German scientists Erwin Neher
and Bert Sakmann invented a revolutionary electrode
method called the "patch clamp technique" for this they won the Nobel
Prize for Physiology and Medicine.
"The technique, which involves removing a tiny piece of a
cell's membrane with the end of an exceptionally fine-tipped electrode, allows
researchers to investigate the molecular channels in membranes through which
ions flow in and out of cells. By applying voltages to such
"patches", Neher; Sakmann
and others found that they could trigger tiny ion currents across the patches
as specific voltage-sensitive channels opened up in the membrane.
Each channel is a protein embedded in the cell membrane and behaves
like a frontier post on a border; only letting certain types of ions across
when they receive the appropriate signal-in this case a change in voltage. When
sodium channels open up, letting sodium ions enter at a certain point along a
nerve fibre, the voltage further along the fibre falls, encouraging more sodium channels to open.
The end result is a wave of voltage change which moves down the fibre, an action potential. In the late 1980s,
physiologists using the patch clamp technique also discovered voltage-sensitive
channels in the non-nervous tissues that pass action potentials. But the
greater surprise, was finding them in animal cells which do not carry action
potentials. And just as this revelation was sinking in, voltage-sensitive
channels came to light in plants. A group of biophysicists and plant scientists
led by Nava Moran at the National Institute of Neurological Disorders at
In animals, action potentials are not confined to conventional
excitable tissues such as nerves or muscles. Most epithelial and embryo tissues
pass action potentials using gap junctions, and in some cases behave more like
plants. Epithelial tissues use calcium ions instead of sodium ions, and embryo
cells destined to become nerves or muscles can change their preference for
sodium or calcium as they develop.
A very important breakthrough was made in 1991 by Daniel Cosgrave and Rainer Hedrich at
the
Another role for stretch-sensitive channels could be to tell
stomata to close when a plant's cells are over inflated with water. In keeping
with this notion, many plant cells, such as Chara and
Nitella, pass action potentials when they swell or
deflate with water. This may mean that stretch-sensitive ion channels help to
trigger these impulses. And perhaps these action potentials be
a way of ejecting surplus ions and water from cells. Similar ideas have emerged
to explain the existence of stretch-sensitive channels in "ordinary"
animal cells, and are currently the subject of much investigation. These cells
also have an activity that has no apparent purpose: their cytoplasm flows
around endlessly in a cycle, sandwiched between the large vacuole in the centre
and the plasma membrane towards the outside of the cell. Whenever a Chara or Nitella cell is touched,
the streaming movement suddenly stops and then, after a short rest, restarts.
Biologists now think they know why the touch stimulus triggers calcium to flow
into the cell, dramatically altering the voltage across the cell's membrane and
driving in yet more calcium. The calcium flood blocks the actin
and myosin protein filaments that power the movements of cells and all their
internal components. In animals, an uncannily similar sequence of events leads
to the contraction of muscle cells.
Stretch-sensitive channels may also help cells detect pressure and
mechanical stress during growth and development. In embryos, for instance, the
channels may "sense" when it is time for a cell to divide. Consistent
with this, young plant cells start dividing when they become inflated with
water.
The idea that action potentials could initiate growth and
development in plants is supported by other lines of research. When a sperm
penetrates a Fucus seaweed egg during fertilisation, the first recordable event is an action
potential, followed later by an electric current driven through the egg via the
Sperm's point of entry and out again at the opposite end. The current appears
to help establish polarity in the egg, and the first cell division is always at
right angles to the current. Similar patterns of electrical growth have been
found in a remarkable variety of fungi, plants and animals and are probably
universal to all living things.
"Stretch-sensitive channels might explain how plants such as
the Venus flytrap detect touch, although there is no direct evidence for this
yet. One could imagine that touching a Venus flytrap, for instance, stretches
channels in the cell membranes of the trigger hair. These channels would then
leak. ions through the membranes, setting off an
action potential that travels through the rest of the trap. Incomplete though
the picture is, one thing is certain:
touch-sensitivity in the plant kingdom is commonplace, and probably ubiquitous.
So how did plants evolve this sensitivity?
The existence of voltage-sensitive and pressure sensitive ion
channels in both plant and animal cells suggest that plants and animals
inherited their ability to sense touch from a common ancestor. Living Signs of
this ancestor are abundant. Bacteria, the forebears of all protist,
plant and animal life-appear to be capable of responding to stimuli by
producing electrical signals.
In 1987, for example, a group of physiologists led by Boris Martinac at the
Interestingly the tension across a cell surface is thought to
affect cell division in animals as well. Experiments designed to track the
cause of asbestos-linked cancer have shown that when cells in culture come into
contact with a microscopic asbestos fibre, they fan
out until a critical tension is reached, when they start dividing. Water
pressure might even control cell shape. Botanists Paula Deschamp
and Todd Cooke at the University of Maryland have found that hydraulic pressure
in the cells of the water plant Callitriche heterophylla determines which of two different shapes the
leaves will adopt: elongated and dissected leaves, or broad and
shortened."
This in not only an intriguing subject but also
somewhat controversial. Many years ago when it was first suggested
that animals may have feeling as well as us humans, there was outrage amongst
the religiously inclined,
‘How dare you suggest such a
thing, you Heretic! We are the chosen of God, these pigs and cows are provided
for us to feed. You will burn at the stake for you traitorous
beliefs!!’ they would yell at the unfortunate scientists.
And today do we dare suggest that plants also have feelings?
Vegetarians will not eat animals as they have feelings, what now will they eat?
And will they start burning scientists at the stake?
Bibliography
Burrell, E and Ellison, J (1986) Plant
Physiology, Elsevier Science publishers Co. Inc.
Cole, P (1995) http://www.angel.co.uk/flytrap
Lloyd, F.E. (1942). The Carnivorous Plants.
Chronica Botanica Co.
Lutz, C. L. and E. Magi. (1980). A preliminary
description of Dailinglonia bogs. U.S.F.S.
Meyers, Dr B (1996) http://www.ccwf.cc.utexas.edu/Gardening
Schuell, D. E. 91976). Carnivorous Plants of the
Schnell-Schnell-Slack, A. (1988). Carnivorous
Plants. Alpha Books Ltd.
Simons, P (1993) The Action Plant, Blackwells
The Secret Life of Plants
by Peter
Tompkins (Author)
Your Brother in Islam,
Burhan