Why can a crow use tools?

The crow is a very intelligent animal, and it is known that there are individuals who take advantage of tools for dexterity and take food. So, why crows can use tools, why is British scientists considering why tools can be used or not in crows?

Scientists Have Found Another Crow That Uses Tools - The Atlantic
http://www.theatlantic.com/science/archive/2016/09/this-crow-nearly-died-out-before-we-knew-it-uses-tools/499724/?single_page=true

St. Andrews UniversityChristian LutzWhen he visited Hawaii in 2013, Dr. saw two Hawaiian glasses sticking tree branches into small holes. This crow is not a wild crow but a raised crow, but it was successfully sandwiching the branches of a long and narrow tree with a straight extending beak, pulling out insects from small holes and supplementing them. Dr. Lutz thought that this is not a litter or the like for this wonderful tree branch of this crow.


Dr. Lutz will in 2012 relate to the use of tree branches by Caledonian glass inhabiting New CaledoniapaperI knew that there was a crow with intelligence that can use tools, of course. However, in a completely different place called New Caledonia and Hawaii, I learned that there are different types of crows that can handle tools the same way, and decided to consider conditions of animals that can use the tools again. Since it is known that it is possible to teach how to use tools in raised crows, it is necessary to check the ecology of wild Hawaiian glasses as to whether Hawaiian glass can use tools, but unfortunate things In 2002 the wild Hawaiian glass is extinct. However, Dr. Rutz seemed to have guessed that the Hawaiian glass skillfully used the tools and that wild Hawaiian glasses would have used tools as well.

In order to investigate the ecology of Hawaiian glass, Dr. Rutz decided to experiment with 109 Hawaii glasses kept in two zoos in Hawaii. When Rutz gets permission for the experiment to the breeding staff, it may be thought that it is absurd but if I tell him that Hawaiian glass has the feeling that we can use the tool, "Yes, we have seen that crows use tools," he said. Actually, Hawaiian glass breeders knew that Caledonian glass knew that they could use tools, so he did not believe that Hawaiian glasses are rare to use tools.

For the crow using two types of tools, Caledonia Glass and Hawaii Glass, the necessary conditions for Dr Rutz 's "Crows to be able to use tools" require "straight beaked beak" and "front of face It is said that it is an eyes attached to. Dr. Rutz thinks that a straight extended beak is necessary to firmly fix the branches of trees and so on, and that a perspective can be obtained by the eyes attached to the front of the face.


In addition, Dr. Rutz points out "The wild woodpeckiness is small" as a common point between New Caledonia and Hawaii. Because there are no woodpeckers, there are many small insects living in trees, and crows have started to use branches of trees as a tool to capture this insect. In addition, we believe that there is no animal predisposed to crows such as hawks and snakes, which is also a factor. In other words, thanks to the privileged environment that there is no natural enemy above the sky and the ground, crows can safely move the neck up and down, left and right and use the tools.

Dr. Rutz cited the above factors and humans may have a feeling of superiority as being "animals that can use tools", but the ability to use tools has physical characteristics and blessings I think that it is one that was acquired with the environment together.