Snake 1

What is the most well-known Native American ceremony involving venomous snakes that still continues to this day? What tribe performs this ceremony and why do they do it?
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Evolution doesn't happen by chance. There must be selective pressure for certain traits to persist from generation to generation. In other words, if these traits become predominant in a species, there must be a reason for it that confers an adaptive advantage to the organism. So, why did it make sense for venom delivery systems to evolve the way they did in front-fanged snakes?
Heloderma are chunky, slow creatures. They trek long distances to find nests and eggs, leaving them vulnerable to predators. Thus the need arose for "keeping" venom: for defense. They also use it for digestion. In Komodo Dragons, they evolved complex venom glands for their "bite-and-slice" technique.
Strike-Induced Chemosensory Searching (SICS) is a stereotyped post-strike behavior that is utilized by many snakes and reptiles, but most prominently in vipers such as rattlesnakes.
After the snake strikes...
1. Quick, voluntary release of prey (to avoid counterattacks)
2. A quiescent period, allowing venom to incapacitate prey
3. Post-strike elevation in tongue flicking rate (PETF)
4. Locomotion while tongue flicking
5. Commencement of scent-trailing.
Tongue - Chemoreceptor; flicks to gather odor molecules

Vomeronasal organ (Jacobson's organ) - Detects and relays molecules to the brain, opens when tongue retracts.

Envenomated prey - Tagged with unique chemical signature. Relocator proteins "tag" the prey, while released by metalloproteinases. Snakes can discern tagged prey from all others.
Specifically, how does a rattlesnake relocate prey (think at the molecular level)?Rattlesnakes trail their stricken prey by tongue-flicking. The vortexes of molecules this creates allows them to detect the location of their prey. These molecules are detected by the vomeronasal organ and relayed to the brain for discernment.What is the scent trail hierarchy in terms of relevance to a trailing rattlesnake?Venom > Integument > Mechanical DamageHow do pitvipers, true vipers, elapids, colubrids, and heloderms, respectively, detect prey?Pitvipers: Heat-sensing facial pits True vipers: Supranasal sacs Elapids: Visual hunters Colubrids: "Cue-Induced Chemosensory Searching" Heloderms: "Prey-Induced Chemosensory Searching"Why do viperids suppress tongue-flicking in the presence of prey, whereas the other groups do not?Because viperids are sedentary ambush foragers, they suppress their tongue-flicking in order to not give away their position and scare away their prey.Name the differences in how viperids and elapids use SICS.Elapids usually do not voluntarily release their prey. There is no refractory period for elapids; they pursue escaped prey immediately. Viperids must strike something to activate trailing. Elapids will search/trail without first striking Elapids use vision/chemoreception to reacquire prey. Viperids only use chemoreception.What are the 3 SICS evolutions proposed by Chiszar that enabled venomous snakes to better handle large, dangerous prey?1. Larger, stronger heads with heavier scales for protection from rodents. 2. Faster acting venoms, which facilitates... 3. A rapid strike-and-release of prey, thus minimizing the potential damage taken.What is the technical term for the "memory" that guides snakes in their prey trailing efforts?Chemical Search ImageApproximately how many people get bitten by snakes annually across the world? About how many in the U.S.?~2-5 million bites per year across the world. ~10,000 of these bites occur in the U.S. and Canada.Approximately how many people die annually from snakebite across the world?At least 100,000 deaths, no doubt more due to the poor record-keeping system.What snakes are responsible for the most bites/fatalities in the U.S.?Rattlesnakes (Mostly Eastern and Western Diamondback Rattlesnakes).Understand the vicious and virtuous circlesVicious Circle: 1. Snakebite victims: Lack of education/awareness, rural communities, community mistrust 2. Antivenom Market: Little profit margin for producers, black market, few producers in marketplace 3. Research + Development: Decreased investment, increased price, weak government/infrastructure. 4. Effective Antivenom: Inadequate supply of antivenom, poor training of medical professionals, weak supply chain. Virtuous Circle: 1. Snakebite victims: Demand for antivenom medicine creates a market. 2. Antivenom Market: A viable market spurs private and public investment. 3. Research + Development: Research and development greatly expands in both wealthy and low-income nations. 4. Effective Antivenom: Robust research and investment leads to more effective medicines and a better supply chain to reach communities.Know the snakebite do's and don'tsDo: Stay calm, clean wound, coat with antibiotic (if possible), apply bandage, elevate wound above heart, get to hospital as soon as possible, describe snake that bit you so the correct antivenom can be administered. Don't: Freeze wound, shock wound, suck venom out, use tourniquet, wash site, slice wound, apply heat.Know the steps of antivenom production1. Obtain the venom (and lots of it). 2. Freeze the venom within 5 minutes of extraction to preserve it. 3. Use some other animal to produce antibodies 4. Purify and concentrate the antibodies from the animal's blood and deliver it to a snakebite victim.Be able to list the 5 ways to mitigate human-snake conflict1. Improve models of outreach and awareness/mitigation 2. Rescue, translocation, and relocation 3. Need for more community outreach/intervention 4. Need for training doctors/first responders/investing in medical infrastructure 5. Sustainable coexistence