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Nudibranchs are gastropod mollusks which live in the oceans worldwide from the polar regions to the tropics. The slugs live in virtually all depths and various species range from the shallow intertidal surf to depths of more than over 700m. Although the majority of nudibranchs are benthic creatures which crawl along the seafloor, some prefer other lives and float upside down under the oceans surface or swim in the water column.
Nudibranchs lose their vestigial shell during a larval phase. To protect themselves they rely on toxins or unpleasant tasting chemicals which are advertised with extremely vivid colors. In order to enliven the gray winter months, here is a little parade of lovely nudibranchs. Enjoy!
Slow lorises are primates from the genus Nycticebus. All five species of slow lorises live in Southern and Southeast Asia. The various species are scattered across a swath of territory running from southern India down across Southern China across the Malay Peninsula and throughout Indonesia. All of the slow lorises are nocturnal and arboreal. Their large eyes help them see at night and their sense of smell is unusually acute. The primates are omnivorous and consume insects, fruit, and plant matter. Their metabolism is very low and their movements are slow and methodical.
Slow lorises are strepsirrhine primates: they have traits which biologists consider to be “ancestral” for primates such as rhinariums (i.e. “wet” noses such as dogs, cats, and bunnies have), multiple sets of nipples, and the ability to enzymatically manufacture ascorbic acid.
Slow lorises also have glands on their elbows called brachial glands which produce a strong smelling secretion. They anoint themselves with this substance and groom it through their fur using their tooth combs (which consist of needle-like teeth on the lower jaw used for grooming). Some zoological literature contends that slow lorises are poisonous and that the combination of their saliva and the secretion from their brachial glands is toxic to humans, however this is not exactly correct. Humans are allergic to slow loris secretions and sometimes go into anaphylactic shock when bitten, yet the secretions are not toxic per se.
In the wild slow lorises are preyed on by large snakes, hawk-eagles, and orangutans (who are evidently not quite as vegetarian as they are made out to be). Predictably, the hugely expanding human population of Southeast Asia constitutes the most serious threat to the various species of slow loris. Many of the little creatures are captured for the pet trade. Since slow loris bites are painful, hunters cut out captured animals’ teeth—an operation which is frequently fatal and, if successful, leaves them defenseless and lacking their principle means of cleaning themselves and interacting with other lorises (since grooming is a part of bonding).
Not only are slow lorises threatened by the pet trade. Local superstition attributes magical protection powers to the slow loris, an so their bodies are burned or cut up for various spells, potions, and nostrums (evidently the protective magic does nothing for the slow lorises themselves). David Adam, detailed some of the consequences of magical myths about lorises in an article written for The Guardian:
As a result [of superstition], the luckless lorises frequently find themselves roasted alive over wood fires while eager people catch the supposedly life-giving liquor that drips out. Bits of their bodies are used in traditional medicine. And legend has it that villagers anxious about traffic safety need only bury a loris beneath a new road to keep it free from accidents.
As stupid and malicious as human reasons for hunting slow lorises are, the most serious threat to the animals comes from deforestation and habitat destruction. Hopefully the rampant destruction of Southeast Asia’s rainforests will halt in time to save our big eyed cousins.
Many reptiles and amphibians are beautifully colored, particularly the poisonous ones. When I was growing up, I had a set of field guides of the creatures of North America. Of all the land animals of North America, the animals which I thought were most beautifully colored were the coral snakes. Coral snakes constitute four genera of snakes within the family of elapid snakes (cobras, mambas, sea snakes, kraits, and other poisonous snakes from warm climates). Many coral snakes live in South America and the old world (where some coral snake species are evolving into sea snakes), but I’m going to stick to writing about the gorgeous red, yellow, and black coral snakes of North America. These snakes are brightly colored to warn potential predators that they are extremely venomous. This strategy has failed somewhat when it comes to intimidating humans, who have a collective fascination with pretty colors.
There are three coral snakes which live in the United States. The eastern coral snake (Micrurus fulvius) ranges from North Carolina to Texas (including Florida and the Gulf Coast swamps). The Texas coral Snake (Micrurus tener) ranges from northeast Mexico up through Texas, Louisiana, and Arkansas. The Arizona coral snake (Micruroides euryxanthus) lives in the Sonoran desert through Southern New Mexico, Arizona, and Sinaloa. All species of coral snakes in the United States can be identified by the fact that their red bands touch the yellow bands (which is in marked opposition to mimics like king snakes and milk snakes). Coral snakes from Central/South America and from Asia do not always follow this rule: the black bands can sometimes touch the red bands, or the bands can be colors other than red, yellow, and black–or there might be no bands at all!
Coral Snakes are fossorial predators which spend most of their life just beneath the leaf litter or loose topsoil where they hunt lizards, frogs, insects, and smaller snakes. Baby snakes are 18 centimeters (7 inches long) when they hatch from their eggs. Adult snakes can grow to 0.6 meters (2 feet) in length. Coral snakes can live up to seven years in captivity.
Coral Snakes are extremely poisonous, but they are also shy and retiring. Instead of hanging around biting, they would prefer to escape as quickly as possible. This makes sense from the snake’s perspective, since their fangs are very tiny and they have to chew directly on their prey in order to inject a fatal dose. Since they have tiny mouths, it is not necessarily easy for them to score a direct bite on humans. Additionally their venom acts slowly—at first there is only a mild tingling associated with the bite. Lethargy, disorientation, and nausea set in hours later. In extreme cases, coral snake bites can cause respiratory arrest. Fatal bites are extremely rare: most sources state that nobody has been killed by a coral snake in the US since antivenin was released in 1967 (although I also found allusions to a 2009 case where a man laughed off a bite only to die hours later).
Coral Snake antivenin was solely manufactured by one US drug company, Wyeth Pharmaceuticals (now a wholly owned subsidy of Pfizer Inc.). In 2003 Wyeth ceased manufacturing coral snake antivenin since too few people were bitten to make the product profitable. There is still a small supply left on hand (although the expiration date has been extended twice), but Pfizer does not seem to have any intention of pursuing a microscopic niche market when it has more profitable businesses to pursue. Foreign pharmaceutical companies continue to produce coral snake antivenin, but they do not sell it in the United States because of prohibitive licensing and regulatory costs (hooray! the United States health care system is unsolving problems which were figured out 40 years ago!).
*Don’t be this guy.
Since prehistory, cinnabar (mercury sulfide) has been sought after for its brilliant red-orange hue. Crushed into a pigment, this mineral becomes vermilion, and it is one of history’s great colors. The bright red-orange of vermilion is unmistakable and takes pride of place in many—maybe most–of the great paintings created prior to the introduction of modern cadmium paints. The villa of the mysteries in Pompeii was painted with vermilion. Medieval illuminators made extensive use of vermillion to color the bibles, codexes, and prayer books of the times.
In the 8th century, Chinese chemists discovered how to artificially synthesize cinnabar. The alchemists of medieval Europe mastered this trick later in the 12th century (after which both painting and chemistry made great strides forward). The brightest reds in the great masterpieces of Renaissance art are vermillion as are the brightest reds in the masterpieces of Baroque, Rococo, and Romantic painting.
Because of its high mercury content cinnabar is very toxic to humans. People affected by mercury poisoning develop tremors, violent mood swings, and tunnel vision. They lose first their hearing, then their eyesight, and ultimately their sanity and lives. The Romans knew these problems were associated with cinnabar mining and so they sent criminals and war slaves to man the mines of Spain and Slovenia. Such wretches had an average life span of only three years.
Because of its magnificent red color, and because it could be refined to yield liquid mercury (which was regarded as a magical regent of life) cinnabar was thought to be one of the keys to the fabled elixir of life. Taoist charlatans and magicians made extensive use of raw cinnabar for allegedly rejuvenating cups, trinkets, and potions. Contrasting this paragraph with the one prior to it yields an obvious irony: the magical life giving elixirs quaffed by Taoist mystics were toxic. Many Chinese emperors, aristocrats, and elites probably greatly shortened their life by becoming too enamored with the deadly beauty of vermilion
Spring has not sprung in Brooklyn–not at all. However, as winter marches on and the days slowly become longer, the garden begins to beckon. Nature’s ancient power will not be denied. My garden may be ice and mud but, out there in the wider New York area, the very first flowers of the season have already come into bloom. Looking at the Brooklyn Botanic Garden bloom list reveals that the hellebores have just opened up (unless you are reading this at some later point, in which case its still a great link).
Hellebores are also called Lenten roses because they come into blossom so early. The name is a complete misnomer since they are actually part of the Ranunculaceae family along with buttercups and, um, ranunculuses. The plants are very beautiful. The pure white H. niger blooms even in the midst of frost and snow. Helleborus orientalis is widely grown for the many delicate colors of its flowers. Despite its ghastly name, Helleborus foetidus is known and loved for its pale green flowers which stand out prettily against its dark evergreen leaves. Do not, however, be taken in by the beauty of the hellebores: they contain a very potent toxin. Some species such as H. viridis contain compounds which cause ringing of the ears, confusion, thirst, a feeling of suffocation, swelling of the tongue and throat, slowing of the heart, and ultimately death from cardiac arrest. Even the virginal white Helleborus niger causes burning sensations, oral sores and terrifying gastritis when ingested so do not eat these plants!
Hellebores grow widely across Europe and the near east, however the greatest concentration of species can be found around the Balkans. Many myths and legends have come to be associated with the dangerous plants. The flowers were sacred to Hecate the underworld godess of magic, sorcery, and crossroads. This association with witchcraft and the underworld has made the hellebore the subject of much dark poetry.
In the absence of useful remedies, ancient Greek physicians treated psychological disorders with hellebore. It has been speculated that Alexander the Great may have died from hellebore which he was self-administering. Hellebore holds a further place in history as an early chemical warfare agent. During the Siege of Kirrha in 585 BC, the Greek besiegers poisoned the city’s water supply with hellebore. So many of the defenders were undone by the herb’s purgative effects that the city fell and the Greeks slaughtered all of the inhabitants.
Hmm, that got darker then I intended, my real point was to enjoy the first lovely blooms of the year. Spring is finally on its way!
Nudibranchs are among my favorite animals to look at. These tropical marine mollusks feature extraordinary colors and fantastical shapes which would make the most flamboyant nineteen eighties rock star weep with envy. One of the largest and most powerful nudibranchs is also one of the most beautiful. Hexabranchus sanguineus lives thoughout the tropical waters of the Indo-Pacific Ocean and can be found from the Red Sea to Hawaii. The creature’s common English name is the Spanish Dancer because, when it swims free, it undulates its bright red paradodia in the manner of a flamenco dancer.
Although the Spanish Dancer is surprisingly quick and agile when it uses this means of locomotion, it has an auxiliary method for getting around and can also be found crawling in a much more traditional slug-like manner. The creature grows to be 40 centimeters or larger and has several distinctive color patterns ranging from bright red to bright yellow to pale pink (or sometimes various combinations of these colors).
The Spanish dancer can afford to be extravagantly colorful because it contains toxic chemicals inside its body (again one is drawn to comparisons with 1980’s musical entertainers). Predators therefore avoid the creature as it proceeds about the reef feeding on various sponges and bryozoans. Spanish Dancers are hermaphrodites. Although each Spanish dancer possesses the reproductive organs of both genders, it is very rare for an individual to fertilize itself. When they do mate, the parent carefully deposits a large pink rosette of eggs which is almost as distinctive and lovely as the adult.
The Spanish dancer is sometimes inhabited by one or more Emperor Shrimps. These little arthropods do not help their mollusk host, but neither do they harm it (a commensal relationship). Chameleon-like the little shrimp can adapt to the extraordinary coloring of their vivid hosts.