Underwater photography with the Canon PowerShot D30

Pros:

1. Easy to carry and use. No big heavy case around the camera to open and close near splashing salt water.

2. A good default underwater white balance setting.

3. Takes good high resolution videos at 24 fps, which for most underwater movement speeds is as good as 30 fps.

4. Reasonable (1 to 1.5 sec) shutter lag from button press, which improves ability to take quick photos of moving targets.

5. 25 meters is deep enough for almost all recreational dives around Hawai'i, and is much better than the Nikon AW120, which cannot get to the 70 to 80 foot depths that are common diving here.

Cons:

1. Lacks a manual white balance mechanism.

2. No raw mode.

3. Shutter speed in dimmer light is not very good, due to a smaller lens aperture (f 3.9) than most more expensive cameras.

4. Shutter lag: any at all is a problem when the fish are shy.

The Development of the Adult Brain: Nature on the brain's white matter tract development over the human lifespan.

The human body in general reaches adulthood shortly after sexual maturation: on the average, unless you have a pituitary disorder, long bone skeletal growth ceases by around age 19 and vertebral column growth by age 21. Perhaps a few bones in pelvis and skull continue very slow growth through middle adulthood.

The human brain, like the skeleton, reaches adult volume by age 21, but, unlike the rest of the body, certain portions of the brain, such as the white matter tracts within the brain which serve as communication pathways, are still growing and developing even at age 30, reaching a peak in the early to mid thirties and remaining at a relative plateau until about age 42, according to a new study published in Nature this month. After the early fourties of age, brain pathways slowly lose substance, inverting the upward climb of childhood through early adulthood, as aging occurs.

One brain parameter the authors studied and called "R1" is the inverse of the MRI T1 density. The T1 density of the brain's white matter decreases as more myelin is added to the tracts, since myelin's waxy or fatty component is dark on T1 views of the brain MRI. So the R1, the inverse of T1, increases as the brain grows more and denser communication pathways. The other parameter, diffusion MRI, measures the degree to which brain water is tightly bound within the brain pathways as they run in various directions, and so is a similar measure of brain pathway maturation, but one which seems to deteriorate more slowly with brain aging than MRI measures of myelin lipid density.

------------------------------

ABSTRACT

Lifespan maturation and degeneration of human brain white matter

Jason D. Yeatman, Brian A. Wandell & Aviv A. Mezer

Nature Communications 5, Article number: 4932 doi:10.1038/ncomms5932

Received 06 June 2014 Accepted 08 August 2014 Published 17 September 2014

Properties of human brain tissue change across the lifespan. Here we model these changes in the living human brain by combining quantitative magnetic resonance imaging (MRI) measurements of R1 (1/T1) with diffusion MRI and tractography (N=102, ages 7–85). The amount of R1 change during development differs between white-matter fascicles, but in each fascicle the rate of development and decline are mirror-symmetric; the rate of R1 development as the brain approaches maturity predicts the rate of R1 degeneration in aging. Quantitative measurements of macromolecule tissue volume (MTV) confirm that R1 is an accurate index of the growth of new brain tissue. In contrast to R1, diffusion development follows an asymmetric time-course with rapid childhood changes but a slow rate of decline in old age. Together, the time-courses of R1 and diffusion changes demonstrate that multiple biological processes drive changes in white-matter tissue properties over the lifespan.

Second order vagueness, identity, and biological species: Part IV (troubles for Thomist concepts of essence in biology)

Imagine Hamish McDonald, a Scotsman, sitting down with his Press and Journal and seeing an article about how the "Brighton Sex Maniac Strikes Again." Hamish is shocked and declares that "No Scotsman would do such a thing." The next day he sits down to read his Press and Journal again and this time finds an article about an Aberdeen man whose brutal actions make the Brighton sex maniac seem almost gentlemanly. This fact shows that Hamish was wrong in his opinion but is he going to admit this? Not likely. This time he says, "No true Scotsman would do such a thing."
-- Anthony Flew, Thinking about Thinking, Or Do I Sincerely Want to Be Right, 1975.

Aristotle's biology identified living things--all of them-- as having a kind of soul as their form or essence. There was a hierarchy of such essences, classified by the soul's capacities. Plants possessed a nutritive soul, once which could consume, grow, and reproduce. Animals had these abilities, plus a sense of their surroundings and ability to move in response to their surroundings which plants seemed to lack: As such, they had an animal or "sensitive soul," which in addition to nutritive function had sensation and movement. Finally, humans were unique in having a "rational soul" because they can reason.

Modern biology categorizes life into kingdoms, some of which, like fungi, Aristotle might have considered to have a "nutritive soul." In addition, modern biology includes an extensive body of knowledge about microscopic life forms about which very little was known prior to the seventeenth century. Such life forms often have characteristics which are neither plant nor animal. For example, unlike macroscopic plants and animals, such cells may not undergo the cyclical larval and adult growth and development seen in the life cycle of typical animals, but instead may simply split at a particular size or age into two cells in a process called reproduction by mitosis. Certain species of bacteria may be motile or entirely non-motile in their normal colony formations (see here for example), so that presence or lack of motility may overlap both plants and animals within a fully normal variety.

To avoid controversy and the category errors that might otherwise be made about such microorganisms, biologists have chosen to place the archaea and the bacteria in their own classification domains, entirely separate from the hierarchy into which Aristotle classified the souls of plants and animals.

The "no true Scotsman fallacy," as described by Flew at the top of this posting, rests on a purported disagreement about the essence of a true Scotsman. Hamish is certain that certain standards of behavior are essential to being a Scotsman, and when confronted with a counterexample to his belief, he retreats in argument to suggesting that the exception is an aberration from what the true essence must be.

Consider now the possible plight of a biologist discussing the classification of bacteria with a classicist who wishes to determine whether a particular bacterium has a plant or and animal soul? The dialog might go this way:

C: So a spirochete is an animal. Look how it evades attack by white cells by moving away from them. It's alive and responds to its environment by moving from place to place. So it has a sensitive, animal soul.

B: Well, actually, spirochetes are bacteria. They are neither plants not animals, since they lack things like membrane-bound organelles such as mitochondria or a nucleus, and their DNA lacks histones and is structured differently from that of animals. So even though they may be motile, that does not make them true animals.

C: This sounds like the true Scotsman fallacy. I know an animal when I see one. What justifies using little differences like those to split one kind of animal off from others, as not being an animal at all?

B: Let's pretend that on a faraway asteroid there is a group of mining robots, built long ago by a group of nanotech-savvy aliens. The bots can grow and repair themselves and can reproduce themselves. They respond to the asteroid environment by mining it, and they can move around on its surface freely. They are not conscious, but function well at mining. So, they must, I think, have animal souls?

C: No, because they would be machines. They are not alive. Aristotle was classifying life, not tech. They don't have souls.

B: How is what you are saying different from my telling you that bacteria and archaea are neither plants nor animals, but an entirely different category of life than the ones Aristotle wrote about? Who is to say Aquinas would not agree that bacteria lack animal souls?

-----------------------

In the true Scotsman story, Hamish has an ulterior motive in saying the Aberdeen evildoer cannot be a true Scotsman: he wishes to maintain a high opinion of the morals of his own ethnic group. Similarly, the Thomist has an ulterior reason to maintain the primacy of Aristotle's classification system for species: Aquinas identified the Christian concept of the immortal soul with Aristotle's rational soul, the form of the human body. Since Thomism identifies the Christian soul with a theoretical construct of Aristotle's biology, Aristotle's biology becomes a part of Aquinian theology.

Where does the issue of vagueness in the biology of species come up here? Vagueness in deciding just what a species is or exactly which organisms are that species might mean that it's vague whether or not a particular animal has a particular form or essence. Aquinas' essentialism allows each living thing to have only one essence, and so if what essence a living thing has is vague, just what single essence it has may also be uncertain and subject to error. Would this mean that whether a given person-- say, a premature infant-- had a human soul, or was in fact truly human, was also subject to error? Vagueness in biology should not lead to vagueness in ethics, should it?

I think that such pseudo-canonization of Aristotle's biological theories looks like a mistake, and think that medieval theology might have been better off if Duns Scotus had won in the controversy referenced in this link.

Scotus' view of human biology and psychology was more nuanced and less monolithic than Aquinas', as it conceived of living things to be composed of many modular essences united by a unifying principle--a principle we might now call its DNA. His ideas about natural kinds, it seems to me, have much in common with today's medical concept of the human body as a composite of many separate yet intertwined systems and organs. A more nuanced, combinatorial view of essences allows room for vagueness. Too bad that instead a monolithic, unitary "just one form for each living body, and nothing else in a living body has any form" Aristotelian doctrine held sway in medieval science for so many centuries.

Second order vagueness, identity, and biological species: Part III (some digressions about value superposition).

There may be considerable similarity between the modality expressed in the vague boundaries of of rough sets and the modal expressions sometimes used in theories of possible worlds in quantum mechanics. This may not be too surprising, since probability can be modelled as a calculation over sets of possible worlds. Because of this similarity, I would like to digress briefly in this next section to discuss some of the models of quantum superpositions considered as set theory and how they can deal with identity.

Under the well accepted "standard" Copenhagen interpretation of quantum mechanics, particles which may have more than one quantum state as an outcome of measurement exist only as a discontinuous probability function, which is sometimes visualized by imagining the state of the unobserved particle to be a ghostly overlay of all its possible observable states simultaneously. For example, a particle that might be observed in state A, B, or C may be considered to be in a pseudo-state where it is simultaneously in states A, B, and C. Such a particle is said to be in a superposition of states. Measurement or other interactions with the particle's environment are said to collapse the superimposed states to produce a single real state which is the result of the observation.

If we take such a concept from quantum physics, we may consider what I'll call quantum superposition sets, or QS sets. A QS set is a set of possible values, such as x = { 2, 3 ,4 } and y = { 1, 2, 3 }. A variable that is a QS set can collapse, whereupon it will take a single value, exactly one element from the set. Two variables which are QS sets are vaguely equal if they have any element in common, so that on collapse, they might take on the same value, and two such variables are vaguely unequal if on collapse they may take on different values.

Consider the sets QS_a = {A, B, C}, QS_b = {A, B, C}, QS_c = { A, D, E },and QS_d = { F, G, H }.

QS_a is both vaguely equal and vaguely unequal to QS_b and QS_c and is non-vaguely unequal to QS_d. Note that even though by the laws of identity QS_a is exactly equal to itself (since it collapses itself as one object), but, because two otherwise identical QM objects may "collapse" in different ways, QS_a is not exactly equal to QS_b when the identity function depends on measurement after collapse of the waveform, even though they are the same superposition as a set prior to "collapse."

On the other hand, QS_a and QS_d do not share any possible values upon collapse, so it is quite definite that they are not equal.

Similarly, two rough sets that share their inner and outer boundaries and have elements in the zone beyond the inner boundary should be considered both vaguely equal and vaguely unequal, and two sets that do not share their inner boundaries and are not empty sets must be definitely unequal.

How do we apply superpositions to the biology of species? Let's consider the hypothetical assignment of bears in a study sample to two different species based on three different criteria for a species decision: fur color, diet, and biome type. Let's make a chart of possible outcomes of our sampling. Our starting criteria for species G bears is that they are brown omnivores that live in the woods, and for species P bears we have the criteria that they are white carnivores that live on the tundra. Our data will mostly but not completely fit that partition. Here is hypothetical data:

outcome 
label    | color | diet | biome  |count
         |       |      |        | 
A        | brown | omni | woods  | 21
B        | brown | omni | tundra | 1
C        | brown | carn | woods  | 1
D        | brown | carn | tundra | 5
E        | white | omni | tundra | 1
F        | white | carn | woods  | 1
G        | white | carn | tundra | 27
H        | white | omni | woods  | 4
I        | black | omni | woods  | 3
--------------------------------------
                               N | 64

Here, a given bear we choose to observe is, until fully observed, an observation that may be considered to be in state { A,B,C,D,E,F,G,H,I }, until our observations "collapse" the bear's datum into one of states A through H. If we were observing a population that included pandas, we might need to include vegetarian diet and add categories allowing for this, and if we were to judge a species based only on one of two "light or dark" fur colors, we might need only an A and a B category. Thus, with rough sets, the decision as to what criteria determines our inner and outer bound determines what part of the sample is vaguely classified and what part is well defined.

Consider a researcher who hypothesizes that the sole determining factor between bear species is their biome. He has no trouble separating bears into two sets: { A, C, F, H. I } and { B, D, E, G }. According to that researcher, the P species is composed of bears fitting { B, D, E, G }. However, a researcher who sticks to the criteria that the two species are determined by differences in three traits: color, biome, and diet, would find that the P species of bear would only include 27 bears and the G category only 21 bears, leaving 16 bears to be classified, perhaps, by biome alone, about which we are uncertain. These 16 remaining bears would then fall in the "vague" zone, outside of definitely-P bears and definitely-G bears, and by then using only biome criteria to place the remaining bears, 7 would be in the vague zone for P bears, and 9 would fall into a vague zone for G bears.

If we determine that diet is determined mostly by available food in the biome and that black bears are just really dark brown bears, and so decide to collapse the species definitions into white tundra P species bears versus black or brown woods dwelling G species bears, we than have 28 P species bears and 25 G species bears, with 11 remaining in the vague zones (using biome for the remaining species criteria to assign 6 brown tundra vague P bears and and 5 white woods vague G bears, respectively).

The rough sets as used for that last classification are P = { { E G } B D } and G = { { A C I } F H }, with the inner sets contained in two sets of parentheses.

What conclusions might a biologist draw from the above data? Unless this data is collapsed to look at a single criterion such as biome, there are many data points that do not fit cleanly into our hypothetical categories. Are P and G bears really separate species? We are not classifying bears cleanly using the data we have collected, and so we may need to find better criteria for categorizing bear species.

Second order vagueness, identity, and biological species: Part II (Vague Identity)

Gareth Evans (1978) published a well known article suggesting that to accept vague objects leads to a paradox in their identity relations. With some expansion of the later steps in the proof, where Evans moves more quickly than I feel comfortable following, the argument can be summarized as follows:

Let (vague) be symbolized as a nabla with ∇,and let this be a specifier that an object or its relations are vague. Let the Delta, Δ, symbol then indicate that a relation with that object is definite. Also, specify that ∇x ↔ ¬Δx and Δx ↔ ¬∇x. Assume that two vague objects, a and b, are possibly equal, but that it is then vague that they are equal. Then

I. ∇ a = b

The next part of Evan's argument is rather tricky, and involves running a lambda substitution backwards. A lambda substitution means we take a formula or sentence in logic and modify the formula by replacing each occurrence of a variable, like x, with another value or phrase. The method is called a lambda function, and is written like this:

λx | expression | y

where y is substituted into the expression within the straight brackets wherever x is found. So for example,

λx | 2 x + 1 | 5 = 2(5) + 1 = 10 + 1 = 11.

Now, to run the lambda substitution backwards. We can see that with the above expression,

9 = 2(4) + 1 = λx | 2 x + 1 | 4

Here we will specifically consider a lambda function M, which we define as λx | a = x |.

Now, consider the lambda function λx | a = x | b which can be written by substituting b for x as a = b. Similarly, we can say, given that ∇ a = b, that:

II. ∇ λx| a = x | b, or ∇ M b

Next, Evans considers that by identity,

III. Δa = a

which he rewrites, again via a reverse lambda transformation, as

IV. Δ λx| a = x | a, or Δ M a

Now, if the vague, ∇ and the definite, Δ are considered logical inverses, we then can transform IV into

V. ¬ ∇ M a

Combining V. with I., we get

VI. ¬ ∇ M a AND ∇ M b

So, by the non-identity of non-indiscernibles, we have

VII. a ≠ b.

...which produces logical contradiction unless we allow ∇ and Δ to not be true inverses of each other.

Note here that the final conclusion, a ≠ b, drops the vague and definite modal qualifiers. This is because it is a meta-statement about the identity relation's truth values, independently of the object's vagueness. Fortunately, Evan's contradiction is avoided if we allow the the definite to be a special case, or subset, of the vague. In that case, the inverse of vague identity is not crisp or definite identity, but just nil, the null set of lack of all identity. We can define inequality for sets such that two rough sets with the same upper and lower bounds are not generally exactly equal, but may be vaguely equal, so that both I and VII can be true of two rough sets.

Any given rough set a is always such that a = a, but even if rough set a and rough set b have the same bounds, they may not contain the same elements within their vague regions (though they might), and thus it is also true in general that rough set a is nonequal to b. Of course, a may be strictly equal to b if they are both empty sets or if they have the same elements within their lower bounds and no elements within the vague zone between their upper and lower bounds. Such sets would of course be crisp, or ordinary, sets as well as vague sets, since we are allowing conventional sets as a special case of vague sets.

Aloha Friday: Black Sand - Ledward Kaapana

The beautiful old Kaimu black sand beach near Kalapana, in the Puna district of Hawaii's Big Island, was featured in the movie South Pacific. That wide beach, with its coconut trees swaying in the trade winds, was situated near Kalapana on the east side of Hawai'i. It is completly gone the past couple decades, buried under 25 meters of lava. So too gone is the little village of Kaimu, destroyed with the beach in 1990 by a lava flow from a vent of the volcano of Kilauea. There is a new beach below nearby cliffs, but it is a mere shadow of the beach my wife and I visited on our honeymoon in 1985.

The Hawaiians called Pele of the volcano "ka wahine ai honua," "the woman who devours the earth." Perhaps calling flows from Kilauea a "devouring" is not completely fair, since the volcano makes new land as it devours the old, yet that is poor comfort to those whose homes are gone. God help the villages of south Puna, especially Pahoa, during the current lava flows.

Second order vagueness, identity, and biological species: Part I

Previously on this blog, I've discussed how sometimes whether an organism is a member of a category is vague, and that it may even be vague whether something like a virus is alive. This was vagueness about the classification of a certain life-form. There is also vagueness about the species category itself: exactly how many species are there on the Earth? This is not a question that admits of a clearly correct, precise numerical answer. Such is second order vagueness about species.

The Stanford Encyclopedia of Philosophy contains a nice summary of current models of biological species, and concludes, it seems to me, on an uncertain and potentially paradoxical note, by noting Darwin's writings on the species concept. Says SEP:

Thus far it has been suggested that Darwin doubted the existence of the species category because he doubted the distinction between species and varieties. What about those taxa[1] called ‘species’ by competent naturalists, are they real taxa for Darwin? It seems that Darwin was a realist when it comes to taxa. A passage at the start of the Origin's chapter on classification, Chapter 13, confirms this. Darwin writes that “[f]rom the first dawn of life, all organic beings are found to resemble each other in descending degrees, so that they can be classed in groups under groups. This classification is evidently not arbitrary like the grouping of the stars in constellations” (1859[1964], 411). Those taxa (“groups”) identified by competent naturalists can be real. And classifications of groups within groups, if properly constructed, reflect the hierarchical arrangement of taxa in the world. Thus, Darwin's skepticism of the species category did not extend to taxa and those taxa called ‘species.’

Thus, from Darwin's view, biological taxa of the type considered species are definitely species. Yet most classifications of species overall may be vague or dubious, since there is no abrupt dividing line between varieties of a species and different species.

Let us now consider a set

Set S_taxa = { the set of all taxa considered species by Darwin's criteria }. This an ordinary, non-vague or crisp set, with well defined members.

Now, compare set S_taxa to set

S_all = { the set of all species }, which is then a vague or poorly defined set.

Now, we stipulate that S_taxa is a proper subset of S_all. Then S_all is a vague set, but it has at a minimum the members of S_taxa, plus a vague number of other species. If we now consider that S_all cannot be larger than the number of individual living things, at the largest, we can establish an upper bound on the members of S_all[2]. We then can use the methods of mathematics to investigate S_all, the set of all species, as a rough set.

[1] Taxa is here defined as a well tested, working classification unit for organisms in biology. An example would be a federally defined endangered taxa and species such as Dermochelys coriacea, the leatherback turtle.

[2] I don't pretend to know the exact upper bound here, but to create a definite upper limit we can certainly choose a definite integer bound.

More on A-T essentialism: Mereology bites chemistry.

Feser is a fearless philosopher-writer who enjoys blog-tilting at analytical windmills. I like his prose, but hate his science. His mereology may have jumped the chemical shark

here.

Feser claims that hydrogen atoms cannot be present in the body, or in water, except in virtual form, because the hydrogen in water cannot burn. Here Feser makes unjustified assumptions about the so-called essence of hydrogen, based perhaps on what he knows about its behavior. He claims that the property of being able to burn is part of what is essential to hydrogen (an essential property), so that hydrogen that never burns is not really hydrogen (and thus is only "virtual" hydrogen). This puts Feser in the position of saying, in contradiction to basic high school chemistry and basic physical science since the 18th century, that water is not made of the substances or elements hydrogen and oxygen-- it is just the substance water, and the different elements of a compound like H2O do not really exist in the compound.

Taken in an empirical, scientific sense, this is the sort of nonsense which could send the scientifically trained screaming toward logical positivism. One can only hope that Feser metaphysically equivocates on what he means by such words as "hydrogen" (a substance unknown to humankind prior to 200 years ago).

Making assertions like this one (that there is no actual hydrogen in water), based perhaps on philosophical beliefs about what Aquinas might have thought of hydrogen, is to virtually torture both Aquinas and hydrogen :). Mercifully, it is instead a fact that hydrogen's burning in air is extremely context dependent, and so it is therefore more of a virtuality that all hydrogen burns, more of an accident (or human design) if a given bit of hydrogen happens to actually burn! Why, then, should burning be essential to Feser's essentialist definition of hydrogen as a substance?

Most of the hydrogen in the galaxy is located in stars, in plasma form, which NEVER burns by combining chemically with oxygen! If the defining, essential property of hydrogen is to be found in its usual behavior, and it is that average or usual behavior which is to define its true essence, then hydrogen should instead (since most is to be found within stars) be defined by its ability to FUSE-- into helium. Not to burn in air. Or perhaps, since hydrogen's main tendency in human experience (context change) is to be a component of water, then being in water as a compound should be the definition of the substance hydrogen on the earth, not burning.

To be factually correct here, even as an essentialist, one needs to go back to the high school chemistry curriculum. Hydrogen is the substance which in its atomic state is composed of one proton, 0 or more neutrons, and one electron. Its behavior beyond that is HIGHLY CONTEXT DEPENDENT and should not be essential to what an atom of hydrogen is, actually or virtually.

Having Feser's hypothetical essences of things like hydrogen pop in and out of existence as things are combined and extracted seems mereologically silly, though it's conceivable. This is an example of the absurdities which emerge from the A-T thoretician's practice of accepting a particular definition of the essence of a thing as an authority in science, to the point that he then forces all other knowledge one has about that thing into the Procrustean bed of his definition of its essence, as I complained previously about Oderberg here.

If things indeed have essences, then those essences are likely constantly overlapping, the same way that quantum waveforms in physics can be seen as constantly overlapping in ordinary materials. Why is this overlapping of essences a problem for A-T metaphysics? And why must such substances be able to exist independently, "in themselves," in a philosophy that requires sufficient causes for everything (God excepted but that's beside the point), including substances? Why can't a substance exist at least partly because of the overlapping substances of which it is composed?

Much in Feser's metaphysics badly needs updating for the new millenium.

Caramboxin in Kidney Failure: Why you avoid star fruit if on dialysis.

I had always been told that the reason to avoid eating carambola (star fruit) if you have end stage renal disease and need dialysis is because of the oxalate. Yet many Hawaiian plants, such as taro, are rich in oxalates to the point they are inedible until well soaked or cooked to partly remove the soluble portion of their oxalic acid. Why is the warning only for star fruit, which contains so little oxalate (yet much more than average for a fruit) that it is easy to eat fresh from the tree?

The answer seems to be that it is not the oxalate, but a neurotoxin, caramboxin, which is normally rapidly removed by the kidneys, but hangs around in the body with kidney failure enough to penetrate into the brain, where it causes encephalopathy with confusion, nausea, vomiting, hiccups (hiccups are uncommon with other encephalopathies but are seen in about 80% of cases of caramboxin encephalopathy), and in extreme cases seizures or coma, rarely death. So enjoy starfruit--unless you are on dialysis for kidney failure!

-----------------------------------------------

ABSTRACT

Garcia-Cairasco, N., Moyses-Neto, M., Del Vecchio, F., Oliveira, J. A. C., dos Santos, F. L., Castro, O. W., Arisi, G. M., Dantas, M., Carolino, R. O. G., Coutinho-Netto, J., Dagostin, A. L. A., Rodrigues, M. C. A., Leão, R. M., Quintiliano, S. A. P., Silva, L. F., Gobbo-Neto, L. and Lopes, N. P.

Elucidating the Neurotoxicity of the Star Fruit.

Angew. Chem. Int. Ed., 52: 13067–13070 (2013).

doi: 10.1002/anie.201305382

Caramboxin: Patients suffering from chronic kidney disease are frequently intoxicated after ingesting star fruit. The main symptoms of this intoxication are named in the picture. Bioguided chemical procedures resulted in the discovery of caramboxin, which is a phenylalanine-like molecule that is responsible for intoxication. Functional experiments in vivo and in vitro point towards the glutamatergic ionotropic molecular actions of caramboxin, which explains its convulsant and neurodegenerative properties.