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8 Fascinating Extinct Animals

Published September 18, 2012 in Love For Earthlings, What's New |
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In just the past few centuries, several of the world’s most fascinating animals have disappeared completely from our planet. Though some are certainly just the natural course of things, most of the animals on this list became extinct through human activity. Here are some truly fascinating but extinct animals…

1. Tasmanian Tiger

Though its name and appearance may suggest otherwise, the Tasmanian Tiger was not a tiger at all, but a marsupial. They became extinct on the mainland of Australia before the arrival of Europeans, but persisted on the island of Tasmania, which is famous for the Tasmanian tiger’s close relative, the Tasmanian Devil.

2. Elephant Bird

Measuring in at a whopping 10 feet tall and 880 pounds, the four species of elephant birds that lived on Madagascar were once the biggest birds on the planet. It’s unclear exactly when and how these massive flightless birds became extinct, though it is likely that human activity wiped out the elephant bird in the 17th century.

3. Quagga

When European naturalists and explorers first ventured into the plains of South Africa, they encountered the Quagga and its close relative, the zebra. Because the two species’ stripes varied so much between individuals, it was difficult to tell whether they were simply variants of the same species or distinct from each other. Before they were sorted out into two distinct species, unfortunately, they were hunted into extinction. The last known Quagga died in captivity in 1883.

4. Baiji

The Baiji dolphin, native to China’s Yangtze River, is thought to have only recently become extinct. With the rapid industrialization of its native waterway, the Baiji’s population suffered considerably. About 5,000-6,000 of the dolphins were living in 1950, and, during the last official survey in 2006, none were found.


5. Steller’s Sea Cow

Sea cows were the epitome of the “gentle giant” — something that, ultimately, led to their swift extinction. Growing to about 30 feet long, the slow-swimming sea cow was once abundant across much of the North Pacific. After less than 30 years of hunting by European seal hunters, fur traders, and sailors, Steller’s Sea Cow became extinct in 1768.

6. Irish Elk

With no living relatives alive today, and the latest fossil record dating back 7,700 years, it’s hard to fully imagine the Irish Elk today. Well, maybe not: picture a deer, only bigger. A lot bigger: the Irish Elk was, in fact, the largest deer to ever live, averaging about 7 feet just up to its shoulders, not to mention its nearly 90-pound antlers that had a width of 12 feet.

7. Passenger Pigeon

With a population once estimated to number in the billions, likely one of the largest bird populations in the world at the time, it’s astounding to consider that the North American Passenger Pigeon became extinct in just a century. So how exactly did that happen? Well, the pigeons were a cheap and abundant source of meat — an ideal protein source for slaves and the poor. The birds grouped together in massive flocks, where it was easy to kill many, usually several thousand, at once. Though conservationists attempted to save the bird, the last surviving passenger pigeon died in captivity in 1914.

8. Dodo

The Dodo bird earns the dubious distinction of being one of the most famous extinct animals of all. The extinction of the flightless bird opened the eyes of humans to the role we have in the demise of a species, or “[going] the way of the Dodo.” Native to the tiny island of Mauritius, which was uninhabited before the 1500s, the Dodo bird was unaccustomed to, and thus unafraid of, humans. This made them easy prey, and led to their extinction in just about century.


Scientists Declare: Animals Are as Aware as Humans

Published August 26, 2012 in Love For Earthlings, What's New |
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An international group of prominent scientists has signed The Cambridge Declaration on Consciousness in which they are proclaiming their support for the idea that animals are conscious and aware to the degree that humans are — a list of animals that includes all mammals, birds, and even the octopus.

While it might not sound like much for scientists to declare that many non-human animals possess conscious states, it is the open acknowledgement that makes it big news here. The body of scientific evidence is increasingly showing that most animals are conscious in the same way that we are, and it is no longer something we can ignore.
It is also very interesting to note that the declaration is the group’s acknowledgement that consciousness can emerge in those animals, very much unlike humans, including those that evolved along different evolutionary tracks, namely birds and some encephalopods.

“The absence of a neocortex does not appear to preclude an organism from experiencing affective states,” they write. “Convergent evidence indicates that non-human animals have the neuroanatomical, neurochemical, and neurophysiological substrates of conscious states along with the capacity to exhibit intentional behaviours.”
Consequently, say the signatories, the scientific evidence is increasingly indicating that humans are not unique in possessing the neurological substrates that generate consciousness.

The group consists of cognitive scientists, neuropharmacologists, neurophysiologists, neuroanatomists, and computational neuroscientists — all of whom were attending the Francis Crick Memorial Conference on Consciousness in Human and Non-Human Animals.

The declaration was signed in the presence of Stephen Hawking, and included such signatories as Christof Koch, David Edelman, Edward Boyden, Philip Low, Irene Pepperberg, and many more.

The declaration made the following observations:

  • The field of Consciousness research is rapidly evolving. Abundant new techniques and strategies for human and non-human animal research have been developed. Consequently, more data is becoming readily available, and this calls for a periodic re-evaluation of previously held preconceptions in this field. Studies of non-human animals have shown that homologous brain circuits correlated with conscious experience and perception can be selectively facilitated and disrupted to assess whether they are in fact necessary for those experiences. Moreover, in humans, new non-invasive techniques are readily available to survey the correlates of consciousness.
  • The neural substrates of emotions do not appear to be confined to cortical structures. In fact, subcortical neural networks aroused during affective states in humans are also critically important for generating emotional behaviours in animals. Artificial arousal of the same brain regions generates corresponding behaviour and feeling states in both humans and non-human animals. Wherever in the brain one evokes instinctual emotional behaviours in non-human animals, many of the ensuing behaviours are consistent with experienced feeling states, including those internal states that are rewarding and punishing. Deep brain stimulation of these systems in humans can also generate similar affective states. Systems associated with affect are concentrated in subcortical regions where neural homologies abound. Young human and non-human animals without neocortices retain these brain-mind functions. Furthermore, neural circuits supporting behavioural/ electrophysiological states of attentiveness, sleep and decision making appear to have arisen in evolution as early as the invertebrate radiation, being evident in insects and cephalopod mollusks (e.g., octopus).
  • Birds appear to offer, in their behaviour, neurophysiology, and neuroanatomy a striking case of parallel evolution of consciousness. Evidence of near human-like levels of consciousness has been most dramatically observed in African grey parrots. Mammalian and avian emotional networks and cognitive micro-circuitries appear to be far more homologous than previously thought. Moreover, certain species of birds have been found to exhibit neural sleep patterns similar to those of mammals, including REM sleep and, as was demonstrated in zebra finches, neurophysiological patterns, previously thought to require a mammalian neocortex. Magpies in articular have been shown to exhibit striking similarities to humans, great apes, dolphins, and elephants in studies of mirror self-recognition.
  • In humans, the effect of certain hallucinogens appears to be associated with a disruption in cortical feedforward and feedback processing. Pharmacological interventions in non-human animals with compounds known to affect conscious behaviour in humans can lead to similar perturbations in behaviour in non-human animals. In humans, there is evidence to suggest that awareness is correlated with cortical activity, which does not exclude possible contributions by subcortical or early cortical processing, as in visual awareness. Evidence that human and nonhuman animal emotional feelings arise from homologous subcortical brain networks provide compelling evidence for evolutionarily shared primal affective qualia.

    Read more about this here and here.
    This story originally appeared on io9.com.