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Why dogs are cuter than wolves

There are many reasons why dogs are consider cuter than wolves by humans. One of these is neoteny, or the retention of juvenile traits in an adult animal. Dogs resemble puppies for most of their lives, with their soft fur and floppy ears. Wolves do not neotenize like dogs do; they reach maturity at 2 years old and remain adults for the rest of their life span. Dogs have also evolved muscles around their eyes to create a "sad eyes" look to manipulate humans into caring for them during their domestication. This look has become so iconic in popular culture that it's now used as a symbol of the dog species.
Domestication is a process of human-led animal selection that results in a change in the behavior or morphology of an animal. It's different from taming, which is when an animal becomes accustomed to human presence and no longer fears humans. Dogs were domesticated around 15,000 years ago, and there are many theories as to why this happened. One theory suggests that early humans began to leave food scraps around their campsites, and the wolves who were drawn to these sites gradually became tamer and more accepting of humans. As time went on, the two species evolved to depend on each other; the dogs relied on humans for food and shelter, and the humans relied on the dogs for protection from wild animals.
If cuteness is just a trait that dogs developed to bond with humans, is it possible for other species to develop same trait in the process of domestication?
An experiment in Soviet Union to domesticate silver fox, shows this neoteny effect. Researchers chose more than a hundred male and female foxes at the fur farm for the study. Tameability was the major criteria for selection. Researchers would then divide the foxes into three categories based on their attitude towards humans. Foxes that were most friendly to human researchers (that allowed to pet them and were interested in human contact) mated, and the resulting offspring were likewise put with others of their kind. They eventually established a new group for foxes looking to make human contact; they would wiggle their tails and play just like dogs do. Most of the newborn pups were subsequently placed in the final category, making them almost identical to canines.
The results of the experiment showed that domesticated foxes displayed following characteristics:
  • multi-colored coats
  • floppy ears
  • short or curly tails
  • narrower skull
  • smaller teeth
Newly bread foxes showed similar abilities to understand human commands as dogs did, which lead to conclusion that it's not the dogs intellectual abilities that made them such good companions to humans, but rather absence of fear toward humans. They also had higher level of oxytocin, which was known to be associated with bonding in both humans and dogs.
Today, dogs are the most common pet in the world. There are estimated to be more than 500 million dogs living as pets worldwide, and this number is growing every day. Dogs have been so integral to human life for centuries that it's hard to imagine a world without them. They've become more than just animals; they're members of our families and friends.

When immune system goes rogue

Immune system is a system of the body that protects it from all foreign substances from the outside (viruses, bacteria, fungi, etc.) and controls the destruction of failed or outdated cells (for example, it is immunity that protects us from tumour formations). In order for immune cells not to destroy the cells of their own body, there is immunological tolerance.

Most healthy poisons in the world

While plants do their best to scare away those who want to eat them by producing all sorts of complex poisons and toxins, ironically, some of them are now used by humans only because of those very poisons.

Banana republic the beginning

One of the co-founders of the United Fruit Company (now Chiquita) was Minor Cooper Keith. He built a railroad in Costa Rica and planted many banana trees along the way to feed the workers. When the government could no longer fund the project, Keith had to come up with something to pay back the huge loan he had received. He decided to start using the newly built railroad to export bananas to the United States.

Appendix - a secondary immune organ

Although appendix is no longer used by humans for digestive purposes it still contains a high concentration of lymphoid tissue. Lymphoid tissue is essential for the immune system and may help encourage the growth of some types of beneficial gut flora.

How to survive if you're slow as a sloth?

A sloth can move slowly, but movement is not his primary defense method. Camouflage is a great way to go undetected. And this is where sloths have become experts over a long period of their evolution.