"Spitting cobras may have evolved unique venom to defend from ancient humans"

 Recently I read an interesting article entitled "Spitting cobras may have evolved unique venom to defend from ancient humans" by Taline Kazandjian, Harry Greene, Nicholas Casewell and Wolfgang Wüster.


 I learned a lot about cobras and their habits. These fascinating snakes are mainly known for their defense mechanism called hooding, when the sides of their necks flare out. However, as the authors write, hooding is not the only defense mechanism of these animals. Some cobras can spit venom up to 2.5 meters away, generally hitting their opponent's eyes with poison. I found out that this unique adaptation had evolved three times independently in a small group of Afro-Asian snakes. Spitting cobras use their venom only for defense, not for preying on other animals.


Scientists have the theory that it was man who influenced the evolution of cobras. The timing of the venom spitting evolution coincides with key dates in the evolution of early human ancestors. This kind of defense must have been stimulated by a very strong selective pressure. Bipedal hominins, human ancestors who walked on two legs almost certainly posed an even greater long-distance threat compared to their four-legged relatives. This required a long distance defense from their serpentine enemies, like spitting.

https://theconversation.com/spitting-cobras-may-have-evolved-unique-venom-to-defend-from-ancient-humans-153570

Komentarze

  1. englishdiary10 marca 2021 00:42

    Very interesting, I love evolution stories but I's also love to read your reflections on it.

    OdpowiedzUsuń

Prześlij komentarz

Popularne posty z tego bloga

Billy Milligan- The most severe case of DID

Obraz
The most severe case of dissociation identity disorder was William Stanley Milligan. Twenty-four personalities have been diagnosed in him. Doctors conducting the medical "investigation" found that Billy's problems were closely related to his childhood and to his stepfather Chalmer Milligan, who not only beat or buried the boy underground, but also raped him and sexually abused. It was the time, when David's personality appeared for the first time, helping him to deal with anxiety and pain. More personalities appeared over time. The primary, original personality was 26-year-old William Stanley Milligan with blue eyes and brown hair, who was not able to graduate from high school. He constantly tried to commit suicide and was put to sleep by others. Next personality was 22-year-old Arthur. He had a dominant role, he decided which personality would be revealed and would take over consciousness. He was intelligent, unfazed, and spoke with British accent. He wore glasses. T
Czytaj więcej

"Five ways the pandemic surge in hand sanitisers may not be great news in the long term"

 Tonight I read an article entitled "Five ways the pandemic surge in hand sanitisers may not be great news in the long term" It is true that the use of hand sanitisers and other antibacterial and antiviral cleaning products has sharply increased worldwide since the pandemic started. It has certainly helped to stop the increase in viral infections, however, it has some side effects. I learned that one study found that the regular use of ethanol to sanitize hands resulted in relatively low but measurable levels of ethanol in the blood. While this was below acute toxicity levels, continued use can result in "chronic toxicity", increasing the risk of health problems such as eczema or skin cancer. It can even be fatal at times. Repeated use of alcohol-based hand sanitizers can cause antimicrobial resistance and increase other infections. Research has also shown that ethanol leaking into lakes, ponds, rivers and oceans can harm aquatic species. I believe that despite the
Czytaj więcej

An incident in the bus

When I was returning from school by bus,  few days ago, I witnessed an unpleasant situation. I saw a boy  at my age who had a broken leg. He tried to get to the exit door to get off at his bus stop but could not do it because the bus was very crowded. Even though he asked passengers to let him move forward, people ignored him. The boy couldn't get off. When he tried to do it at the next stop, the situation was supposed to repeat, but I loudly asked people to turn their attention to the boy and let him get off. They were embarrassed but reluctantly did it and the boy was able to get off and thanked me. I started thinking about the situation. I was wondering if people had not heard him? Was the boy talking too softly? Probably some passengers had not used public transport for months because of pandemia and they forgot about taking care of vulnerable people. For sure, it's not easy to be a senior or a disabled person in the society and to ask others for help every time.
Czytaj więcej