Any undeniable reasons for collection of dead specimens?

I have been asked for specimens of a gecko that might be an undescribed species or at least a new locality (I’m in Iraq at the moment - a lot of research is yet to be done here!), but I feel I can’t do that. For now I’m an amateur herper / citizen scientist, but I’m planning to come back to uni next year to study biology, so I’m afraid that sooner or later I will face this problem anyway.
So my question is: are there any logical and undeniable reasons we need dead specimens in 2021? I would think that, in case of lizards, taking very detailed pictures and taking a DNA sample (for example, a tail, a toe, etc.) should be enough. I know about holotypes, paratypes etc., but isn’t it a bit of a thing of a past, when you needed to bring the physical object itself in order to prove that you have seen it? Moreover, you can always lie about some things (for example about the location where you’ve encountered the organism), so it’s not like having the specimen is a 100% proof of the collector being honest.
Since I’m not a professional scientist yet, I’m sure there are some points I’m missing and I’d like to hear them from you - that would make me feel a bit better about the necessity of killing the animals I truly love. Thanks in advance :)


In short, absolutely. This has been discussed quite a bit on other threads.

Maybe for lizards. But for a vast amount of invertebrates, dissection is needed for species IDs. DNA is only so helpful unless it can be correlated with morphological traits. And so often there are physical traits that are missed the first time around. Being able to revisit specimens (say under a microscope) is the whole point of having types.


There are a couple of reasons why voucher specimens are more valuable than observations, but I think some of the bigger reasons are that you can re-confirm what was initially sampled and perform additional samples (such as tissue composition, etc.) with a voucher animal (whereas data would otherwise be limited to only what the initial observer collected). Imagine if technology improves in a few decades and there’s some kind of interesting test you could perform that would reveal all sorts of new data about a species… but there are no vouchers to perform samples on. In the same way, DNA testing was invented pretty recently, like the 1980s, so who knows what new survey methods we might have in a decade or two.

Additionally, it’s very easy to fake photos, so vouchers are the most trustworthy way to collect data, although they are not perfect either-- they are less prone to error and fraud, and we want the most trustworthy data available (especially when doing something major like changing taxonomy). Those are probably the two most major reasons, both pertaining to verifiability.

There’s definitely a trade-off involved though, especially with rare species which could be hurt by aggressive vouchering, although I’m not sure how often that occurs. I know with plant records, I’ve heard a few researchers complain that their herbarium records have tons of vouchers for wild orchids and things that they suspect led to the decline of an already-rare species… but things were probably done generally less carefully in the past.


Somehow I feel like, if you have to take a piece off a live animal, you should probably not cut its toe off. At least the tip of the tail is more expendable, and hopefully hurts less. Either way, that’s not something to be casual about. Not with a living, pain-feeling animal.

If you wind up needing entire specimens, be sure to learn how to humanely kill them. Freezing isn’t considered to be humane for reptiles (partly for lack of data), but chilling and then freezing has been tested on cane toads and showed no pain signals. You put them in the fridge for a few hours, then freeze them solid.


Yeah, I was actually advised to freeze them, but then I remembered watching a video on how to humanely euthanize reptiles and freezing was NOT a recommended method. What you say makes sense though, because the animal would be likely unconscious after cooling.

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You don’t need to collect/send any kinds of specimens unless you choose to. Those who recommended it are probably just interested, although I wouldn’t expect they’d ask/expect too much if you don’t want to (many people might not want to, especially for a lizard). They may be correct that doing so could help confirm what species it is though. Photos can also distinguish species sometimes but are more difficult for new or potentially new species, also in cases of cryptic species, color variation within species or subspecies, etc.


I collect well-preserved specimens of dead insects; I highly recommend, it’s easy to create a personal unique collection.

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Of course, nobody can push me to do it. I understand that it might be useful for science, because this region is poorly researched and the genus in question (Asaccus) is likely to have many cryptic species. Still, I think it’s fine that I don’t feel ready to do it, especially that I would have to carry the specimens with me over the border and I’m not even sure it’s legal (which makes me wonder how do professional researchers deal with that). But having read the answers in this thread I understand that the non-invasive methods aren’t always enough.


There are very good reasons to collect specimens, even now. This is especially true if the individuals may represent a new species. Why?

You can’t know what researchers 50 years from now will want. Appearance is good, but what about dissections? Sampling surfaces or tissues to learn about pollution? Etc.

Preservation of digital photos and DNA sequences is dependent on the stability of our power grid in the face of both terrorism and solar flares. It also depends on continued interest and on compatibility of hardware and software. Physical collections are vulnerable enough, but they can survive periods of neglect better than digital records.

That said, any collections should be made with awareness of population size and vulnerability.


Type specimens (holotypes, isotypes, etc.) don’t exist to prove one has seen the organism. They exist to define the name. The scientific name goes with the type, not with the description, which may be pathetic or fail to include the details needed to distinguish this species from relatives.


I worked with a herpetologist who was regularly getting morphometric data from lizard specimens that were collected before morphometrics were invented. Data likes these can help to discover and thereby protect unique local populations.


Yes, for a variety of reasons.

  1. You can’t get DNA from a photograph. This can be particularly important if trying to make comparisons between members of cryptic species complexes that are only distinguished by karyotype, call, or other features that cannot be easily seen in a specimen.

  2. It is very hard to reasonably get morphology from a photographed specimen, even with detailed photographs. Issues such as parallax or photo angle can make measurements difficult to confirm, whereas if someone can measure the specimen first-hand this can be easy to determine. This is particularly prevalent if someone wants to measure traits of internal anatomy such as bone or organ morphology that cannot be reasonably measured on live animals (in theory it might be possible to CT-scan them, but that would require potentially putting the animal through a lot more stress due to prolonged captivity and sedation than outright killing). As a result, there would be no way to place the new species in broader comparative analyses of, say, skull shape or other phenotypic characters. Even some external features do not photograph well (e.g., squamation patterns, morphology of the hemipenes, etc.). Some animals are only diagnosable based on internal morphological features (e.g., gill rakers, reproductive morphology).

    There are also many, many cases where there are features the original author considers to be unimportant but later studies might find have phylogenetic or ecological significance. With photos there is nothing a researcher can do to collect data for the species if the original author didn’t take photos of that spot (and researchers always seems to find an important spot that gets overlooked in hindsight when they take photographs for research).

  3. No one can cross-reference your data. Say someone name a new species based on a few photographs. This species has some unusual features that another researcher wants to double-check because they are concerned they may be due to measurement error. If the species was named from a photograph there is nothing the second author can do beyond take the describer’s word for it, and they may have to go to the locality and kill another individual if they want to double-check the author’s results. By contrast if the specimen is preserved in alcohol the second research group can just re-examine the specimen.

  4. It is much easier to fake photographs than specimens. Because Adobe Photoshop is a thing. It is true you can lie about specimen location (I’m looking at you, Meinertzhagen), but it is much more difficult to fake the actual morphology of a specimen. This can happen (e.g., Archaeoraptor, Piltdown Man), but in the aforementioned cases the fact the specimens were fakes was discovered was primarily because other researchers could double-check the specimens firsthand and see that they had been tampered with. This cannot be done with photographs (see: every bigfoot show on cable television ever), the best one can do is say they might be tampered with.

  5. It is very hard to get reliable photographs to show a species’ anatomy without causing the animal severe distress. For a reasonable overview of the specimen you would have to get pictures in dorsal, ventral, and lateral views, possible with close ups of the manus, pes, head, and tail, among other features. This would require handling the animal for quite some time and restraining it in order to get reliable photographs.

As a result, it unfortunately is still necessary to kill specimens in rare cases. And this is coming from someone who tries to avoid causing harm to wild animals during research whenever possible. However, there are some ways to minimize harm. For example, if you find an individual that is already dead or is likely to die of injury or illness, using those specimens is perfectly valid for research purposes. Indeed, this is what some wildlife biologists do for species that they are concerned might be in danger of extinction and thus do not want to harm the living population. For example, the Yellowstone National Park wolf collection is made up solely of individuals that died of natural causes (or quasi-natural, like being hit by a truck) during the initial reintroduction of wolves to Yellowstone National Park. In other cases researchers just avoid collecting physical specimens unless it is necessary for the research (e.g., voucher specimens).

Additionally, when one does collect specimens it is always worthwhile to collect specimens in the most humane methods possible, rather than one that can cause unnecessary harm to the animal.


especially that I would have to carry the specimens with me over the border and I’m not even sure it’s legal (which makes me wonder how do professional researchers deal with that).

This is a very good reason not to do so, in fact. As an amateur, it’s not your job to know the laws or how to deal with them – the researchers asking for specimens should be the ones to sort that out, and then inform you about them. I have no idea about Iraqi law, but it would be very common for a permit to be required for the collection, and likely another for taking them across any international borders. (In fact, depending on the country and the species, there could be one permit for leaving and another for entry.)


This. Paperwork for exporting/importing biological materials is usually pretty strict for most countries. I know of some countries like Argentina which will even confiscate plastic casts of biological materials imported across the border. This could easily get the specimens confiscated when trying to ship them across the border. Which would make the collection of the individuals and their deaths meaningless.


In my high school physics class, we learned to calculate velocity and acceleration using some type of classroom device that made marks on an unspooling roll of paper (use your imagination). We turned our numbers in, then some of the students began throwing their marked spools in the trash. We were admonished by our teacher, “NEVER destroy primary data.”
So there you go. Arrange the keeping of the lizard, if at all possible.

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This whole story reminds me of Ted Pappenfuss, herpetologist at the Museum of Vertebrate Zoology in Berkeley. He specializes in getting reptile specimens from countries where many scientists wouldn’t dare go, especially in East Africa and the Middle East. His story about training Taliban guards to catch lizards for him in the desert in Afghanistan shortly before the 9/11 attacks would be completely implausible if he didn’t have pictures of the whole thing. If you ever need to talk to someone about the logistics of getting lizard specimens out of anywhere, call up Ted.


Others have already given great reasons for why physical specimens are still incredibly important. I’ll add just one general one: we have no idea what scientists will need to know in 10, 20, 50, 100, or 1,000 years from now. Museum specimens have answered questions that the original collectors never dreamed would be asked. CT scanning of preserved specimens is revolutionizing our understanding of the evolution of morphology. Stable isotope analyses of specimens have shown us what past diets and food webs were like.

That said, I would strongly advise you not to collect in this case. As others have noted, collecting is almost always regulated by permits. Especially if you’re in another country, the permitting to export a specimen is complex, even in the simplest of cases, and the penalties for not following the rules could be quite high (ie, forbidden from traveling there again, a night in custody, etc.). Many countries are understandably sensitive about scientists (or non-scientists) coming in and removing their biological heritage.

Also, the point about humane euthanasia is an important one. Cooling and then freezing could be an acceptable alternative form of euthanasia for some organisms, but freezing and then thawing makes a specimen less valuable (tends to ruin the histology and soft tissues). Hopefully if you return to school for this type of thing, you’ll receive training in humane euthanasia, specimen prep, and permitting (though no one likes that, it’s just a necessity) and then you’ll be off and running!


Specimens are the actual physical organism. Photos are a snapshot of the organism.

There are simply no methods or techniques possible to obtain the same data from a printed image of a species versus having the actual specimen available to examine or test. Others above already made the useful points, so I’ll leave it at that.

Generally I only collect new species or stuff that’s suspected to be. One issue in the coming years is a lot of old type specimens are being degraded, damaged beyond use. Which is problematic. The plus of photos is they in theory last as long as digital technology can, which likely outlives most preservation. But again there’s a lot you can’t get from photos.


Some of those early naturalists were quite vague about their type localities (perhaps unaware that species might have narrow ranges?). For instance, the Julia Heliconian. In my guide to Butterflies of the West Indies, it says:
TL: ‘America,’ recte Virgin Isles, St. Croix.
What this means is that Fabricius, the original describer of the species, described it only as coming from the Americas, and someone later on corrected it as the type specimen having been collected in St. Croix.

They need permits. And if you were collecting on behalf of a researcher, your activity would fall under that researcher’s permit; you would need to carry a copy of it, annotated to indicate that you are acting as their agent.

Correct. Hence why we sometimes see papers with a “redescription” – the original description was inadequate, but the type specimens are still available, so a redescription of those type specimens can better define the species. A published name without a specimen is called a nomen nudum – it means “naked name,” and is not valid.


I have heard that some fields, e.g., mycology, have debates about whether it should be possible to name a species based on genetic sequence. If the same microbial fungus shows up in lots of environmental genetic samples but no one succeeds in culturing it (as is often the case) can it still be named? I have no horse in that race, but am curious to see where it ends up.