European Robin
Have you ever wondered why birds fly south for the winter year after year without ever asking for directions? Migratory birds use a magnetoreception toolset to find their destinations. For decades scientists have been trying to pin down the exact physical foundation for the avian magnetic sense. Evidence suggests that birds may be flying in the correct direction according to the earth’s magnetic field through use of a radical pair mechanism that utilizes quantum entanglement.
Two quantum particles that are created together are entangled. When two quantum particles are entangled the polarization will be connected no matter how far apart they are. Another way to say it would be that the particles are different parts of the same entity.
In the back of a birds eye there are several molecules that contribute to magnetoreception. The bird is able to detect signals from these molecules to determine the orientation of the magnetic field. Each molecule contains a radical-pair of electrons photo-excited to a singlet state (entangled) and a nuclear spin that couples to one of the electrons. One of the electrons moves a very small distance, just a few nanometers away where it senses a slightly different magnetic field than it’s companion electron. Chemical reactions are then produced depending on how the field changes the spin of the electron. In theory, these chemical reactions could generate a picture of varying light and dark patterns depicting the earth’s magnetic field to the bird.
In a study that was published in Physical Review Letters in February of this year,  researchers at Oxford University and Singapore University specifically examined the durations of quantum entanglement in the compass systems of the European Robin. This information is significant because of the super sensitive nature of entanglement. 
N@C60 (a Fullerene molecule)
States of entanglement are extremely sensitive and difficult to preserve 
artificially. Fullerene is a designer molecule designed by humans to hold

Schematic drawing of N@C60 
Courtesy of Simon Benjamin of Oxford University
The study found that the collapsing of the singlet quantum state doesn’t take place for 100 microseconds or more. This is significantly longer than any manmade system that’s ever been developed. Even N@C60, a manmade designer molecule, only holds entanglement for up to 80 microseconds. In artificial systems, quantum superposition and entanglement typically decay unless cryogenic temperatures are used. In the case of this Fullerene molecule, the cage of carbon atoms provides shielding from penetrating information from the outside world. If we can some day understand the conditions necessary to prevent this rapid decay it may have applications in cryptographic ranging, clock synchronization, quantum computing or even a quantum internet.
It's marvelous that nature could promote these quantum mechanisms through evolution that are so complex as to provide birds and other plants and animals with another sense altogether by utilizing a piece of natural organic machinery that human beings struggle to even grasp the concept of. With our best minds at work trying to replicate what nature has done entirely by accident via natural selection, our progress as depends on our ability to think outside the box and reprogram our brains to comprehend things not entirely in our comfort zone or our nature given genetic material.