Here's the problem with the current theory of insect olfaction

Here's the problem with the current theory of insect olfaction | Part 1 of 4

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Advancing Eco Agriculture

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@andyyang5675 2 жыл бұрын

Tom's knowledge of insects and how it affects agriculture invaluable

@AdvancingEcoAgriculture 2 жыл бұрын

It's truly impressive; we're glad you see it too, Andy! - The AEA Team

@nicktomasini993 2 жыл бұрын

Interesting stuff. There are a growing number of studies that point to microbiome as the most determinant factor in a plant's resilience to insect herbivory. More so than glucosinolates, jasmonic acid, salicylic acid, brix, etc. Given that we've characterized maybe 50% of secondary metabolites in plants, it is likely that the unknown metabolites, which may be associated with plants growing alongside an intact and functioning rhizosphere and phyllosphere MB, are important pieces to this puzzle. We find that working on a functional soil food web in conjunction with a sound nutritional regimen is a very effective way to manage plant health and resiliency. Foliar Feeding insects acquire microbiomes from the soil rather than the host plant (Hannula 2019) The effects of rhizosphere microbes outweigh host plant genetics in reducing insect herbivory (Hubbard 2018) Conditioning the soil microbiome through plant-soil feedbacks suppresses an an boveground insect pest (Pineda 2019)

@howiegruwitz3173 2 жыл бұрын

Hydroponic sucks without B vitamins. Peat moss is loaded with fungi that produce them. Solution: Grow in peat, and sell B vitamins to hydro growers as a side hustle.

@2100suprafreak 2 жыл бұрын

YESSSS!!!!! People look at me like I'm batshit crazy when I tell them it has to do with electromagnetic signaling. I got my theory from looking at radio antennas having to have specific shapes to pick up specific frequencies. I'm definitely looking forward to the next presentations!

@whiteeaglethefirst Жыл бұрын

Look up Phil Callahans woeks.

@whiteeaglethefirst Жыл бұрын

"works"

@TheFarmacySeedsNetwork 2 жыл бұрын

Just into this about 10 minutes now, so excited! Finally some high-level science for us to learn about insects, plants and their interactions! Thank you so much AEA! Thank you so much Tom dykstra!

@ratemyboard 2 жыл бұрын

Structural engineer here… The second he showed the modal analysis (Fast Fourier transform) of wax before and after a pheromone had attached to it… I was like… That has to be it! Maybe every time something attaches to the wax, it changes the natural frequency of the hairs, so the insects smell the way humans hear! …Haven’t listened to the other ones yet but excited to hear exactly how it works

@TheFarmacySeedsNetwork 2 жыл бұрын

Absolutely excellent presentation! I definitely do not believe the current theory on how insects detect pheromones and smells. As a person who has been into radio since I was a young person, I am very much looking forward to hearing more about frequencies, resonance, vibration and how it and how it relates to insects and their detection of their environment. I had a moth land on my ram pump reservoir a few years back and I noticed the patterns that the moth was creating with its wings in the water trying to get out. Everything in the universe is frequency, everything is frequency. Every frequency has a resonance and a resonant wavelength, I'm very much looking forward to the next three talks. Thank you so much aea and Tom dykstra!

@clwnthr 2 жыл бұрын

Indeed.

@2100suprafreak 2 жыл бұрын

Toss in some sympathetic harmonic resonance, I'm looking forward to these also.

@iwenive3390 2 жыл бұрын

Perhaps the the same peaks you read on the wax test are specific to each pheromone and they have a way of reading it as well?

@enstamud 2 жыл бұрын

How do we access Tom's data if it's not published?

@howiegruwitz3173 2 жыл бұрын

Telepathy

@thegardenfarmer 2 жыл бұрын

I love these videos! The information is awesome.

@Ghanzo 2 жыл бұрын

Fascinating! Looking forward to parts 2-4!

@Zenthanol 2 жыл бұрын

I too have academic specialization in insect physiology, but I have not been able to corroborate Dykstra's claims myself. Without published research and access to data, it is impossible to review the methods and materials used and other parameters in experimentation. In fact this topic is very interesting to me, and interestingly I have not been able to find any recently published research that does corroborate. I have mainly found criticisms or contradictions of Dielectric Waveguide Theory of Olfaction. I am curious to hear Dykstra's thoughts on these points: At 15:21 Dykstra mentions that insect odorant reaction time is faster than insect reaction to stimulus or diffusion through pores biophysically. He asserts that diffusion must happen in less than 12 milliseconds and references some research supporting this. Dykstra mentions at 50:03 that a couple decades ago, the conclusions he came to don't make sense. It is possible that this is because there have been misinterpretations, overlooked research, or imprecise equipment at play which happens even to the best researchers for such a complex topic. It is trivial to find research that shows insect neural reactions to stimuli can be shorter than 2 milliseconds in several sampled insects, according to "High-speed odor transduction and pulse tracking by insect olfactory receptor neurons" in 2014. Dykstra asks at 47:20 if anyone can reach a figure between 1-10 milliseconds. The researchers write: "Here, we show that insect olfactory receptor neurons can have response latencies shorter than 2 ms and resolve odorant fluctuations at more than 100 Hz. This high temporal resolution could facilitate odor-background segregation, and it has important implications for underlying cellular processes (transduction), ecology (odor recognition), and technology (development of fast sensors)." In other words, more precise sensing equipment and techniques has allowed us to tell that reactions are not faster than diffusion speed of odorant-binding molecules. Regarding diffusion time, the same researchers state: "This short transduction time contradicts previous studies that suggested olfactory transduction times between 10 and 30 ms. What makes olfactory transduction fast? Olfactory transduction involves several steps, including diffusion of the odorant molecule through the antenna surface, its binding to an odorant-binding protein (OBP), diffusion through the aqueous sensillar lymph to an ORN dendrite, activation of an odor receptor, and opening of ion channels. Modeling studies suggest that diffusion can delay the initial ORN response by 10 ms. Using available data about OBPs and the sensillum lymph, we estimate that >17% of the odorant molecules should reach the ORN dendrite by 3D diffusion alone within 1 ms of encountering the lymph surface. Diffusion speed might be further increased by pore tubules that connect the sensillum pore with the ORN dendrite. Moreover, OBPs occur at high concentrations (10 mM) in the sensillum lymph of insects, which improves ORN sensitivity and might decrease transduction time." Several of the structures mentioned in the research have not been accounted for in this presentation, which may affect the conclusion. "The structural basis of odorant recognition in insect olfactory receptors" was published in Nature in 2021, and depicted the physical binding of odorants with receptors, proving the receptor-odorant binding theory for insects, and there are some very illustrative graphs and diagrams. The researchers note: "Notably, odorant binding relies predominantly on hydrophobic interactions, which lack the strict geometric constraints inherent to other intermolecular associations (such as hydrogen bonds) that frequently mediate ligand recognition. The distributed arrangement of hydrophobic and aromatic residues across multiple surfaces of the binding pocket further relaxes orientational constraints by allowing odorants to form comparable interactions with many of its faces." The interaction of volatile compounds with the binding pockets are special and allow for quicker detection. Finally, in 1976 the extremely well regarded physicist Dr. Mark Diesendorf published a commentary about the Dielectric Waveguide Theory of insect olfaction of Dr. Philip Callahan called, "Insect Sensilla as Dielectric Aerials for Scent Detection?". It describes the lack of evidence put forth by Dr. Callahan regarding the hypothesized manner by which insect antennae detect infrared radiation from volatile compounds and several incompatibilities with how dielectric waveguides function. Also, that several researchers attempted to replicate previous experiments based on Callahans's approach and were not able to do so, and Callahan's omission of these experiments in the literature. The abstract reads: "Callahan (1975) has espoused a mechanism of insect olfaction in which the antennal sensilla act as dielectric aerials (i.e. waveguides or resonators) in detecting characteristic wavelengths of infrared radiation emitted by excited, "free-floating" odorant molecules. However, no physically or biologically feasible mechanism has been put forward for overcoming the thermal black body background at infrared wavelengths. Antennal rubbing and antennal vibrations cannot play a role because the insect antenna is fixed during electrophysiology. Callahan's proposals for generating coherent emission of radiation are in conflict with basic physics." On experimental results: "To sum up, Callahan (1975) has provided no coherent, self-consistent description of a dielectric aerial method of scent detection which could be considered as a physically feasible mechanism. The onus is on Callahan to cite relevant experiments which support his position, especially since experiments have been performed which rule out the hypothetical mechanism for particular sensilla (Stange and Diesendorf, 1973) and particular insects (Hsiao, 1972). The different responses to enantiomers (optical isomers) observed in single cell and behavioural experiments (Kafka et al., 1973), also rule out a radiation mechanism in these cases. Moreover, although the recent interdisciplinary theoretical investigation of infrared radiation mechanisms of insect olfaction by Diesendorf et al. (1974) (the authors are, respectively, a theoretical physicist, a neurobiologist and an applied mathematician specializing in dielectric waveguide aerials) is listed amongst the references of Callahan (1975), not one of the severe limitations pointed out by them is explicitly acknowledged or discussed in Callahan (1975)." I have not been able to find any published, peer-reviewed research that corroborates Dykstra's assertions. I understand the idea that some people may be such pioneers that they "don't have peers" but anyone can be wrong about something, even an expert, especially in such a complex field, so being able to review and test the research of others helps us understand it and possibly any complications. No subject nor scientist is above reproach and I look forward to seeing more research into insect olfaction.

@clwnthr 2 жыл бұрын

"I have not been able to find any published, peer-reviewed research that corroborates Dykstra's assertions". You might want to give the non-peer-reviewed (read: non-controlled) literature a go.

@Zenthanol 2 жыл бұрын

@@clwnthr Dykstra cited published peer-reviewed research to support his points in this presentation that insect reactions to volatiles are faster than diffusion at 22:21, 30:35, 35:08, 40:02. But I was able to find published peer-reviewed research that overturned the assumptions about diffusion time and reaction based on this research Dykstra cited using newer techniques and equipment. If the data in any research is not made public for review, it's impossible to evaluate. Dykstra's research data isn't able to be evaluated or compared to others, peer-reviewed or not. Researchers like me wouldn't be able to compare to other research. But we both make use of peer-reviewed and published research to make these assessments.

@clwnthr 2 жыл бұрын

@@Zenthanol So-called "published research" today, in any given field, means heavily controlled by interests. There's nothing to do but let people go out there and take their own Brix-readings, etc. and evaluate in that way. Video-document it at best and share it with like-minded people. No matter what though, there are very strong indications for that insects leave plants alone when they're healthy enough. That is still the main point of Thomas' information so far, and we'll just have to wait a bit longer to hear his next very interesting points.

@Zenthanol 2 жыл бұрын

@@clwnthr That is interesting, why do you think Dykstra cited published research to support the point that insects don't use odorant binding? I have documented aphids feeding on extremely high brix (14+) plants myself which agrees with the research literature that is published related to their physiology, so I always found it odd when people make the case that high brix reduces insect presence.

@clwnthr 2 жыл бұрын

@@Zenthanol All "published research" is different. Some is decent, but most studies are very manipulated, so more or less random citations taken out of contexts are no good. A brix reading of 14+ might seem extremely high for us at the moment, but there might be much more room for improvement than anyone expects, and everything still points to the healthier the plant, the less insects. Very few aphids might want to feed on or perhaps just test a 14-15 brix plant, but that by no means devalue the overall importance of plant health or brix.

@topos100 6 ай бұрын

By the way...what is this "watery matrix"?...Is this liquid water, or liquid crystilline water...a al Dr. Gerald Pollack...? I think I know the answer....The "water matrix" is what Thomas is missing...Callahan missed it also...but he did not study mitochondrial water...

@4given-c5h 2 жыл бұрын

So neat. Can’t wait!

@topos100 6 ай бұрын

The hairs/cilia on human cells and hairs in human ears and the hairs on the human body...MUST be well within the infrared range...Actually...the is a paper out their about mammillian hairs as infrared antennae...THANK GOODNESS FOR PHILLIP S. CALLAHAN...