You may have heard about how animals like dogs can detect cancer by scent. Well, another species is trying to make their mark in cancer detection. While they may not be known as the smartest animals (their brain is no bigger than the tip of your index finger), pigeons are trying to change their bird brain reputation.
According to a study published in the PLOS One journal last month, pigeons can be trained to detect malignant areas in breast tissue by simply looking at an image. This type of bird was chosen for the study because they have many of the same visual system properties as we do. The study mentions these underappreciated animals can also tell whether a painting is a Monet or a Picasso.
How did the pigeons let the researchers know which image had cancer and which didn’t? They pecked at one of two buttons on a screen that either meant the slide showed a malignant area or it didn’t. The leaders of the study rewarded the birds when they got a correct answer. In order to avoid skewed results and prove the pigeons weren’t simply responding to what humans were doing in the background, the 16 birds were placed in a box so their focus remained on the screen.
The birds learned from images they had seen before because when the study leaders showed new slides to them, they applied the knowledge they had gained from previous images. At the start of the study, the birds only got 50 percent of the readings correct. Twenty-five days later, they were right a remarkable 90 percent of the time! The speed at which the pigeons learned how to read and recognize breast cancer is astounding considering humans who practice pathology or radiology for a living spend years training their eyes to identify cancer. The results are so positive, in fact, the birds may be considered to fill in to read cancer screenings if a human isn’t available.
Those who practice pathology or radiology shouldn’t worry about their job security just yet. Pigeons have an easier time detecting cancer in higher quality images in comparison to those that were a certain color. The birds had an easier time recognizing calcium deposits that can point to breast cancer, called microcalcifications, but found recognizing density differences in the tissue more difficult. In fairness to the animals, humans often struggle with this, too. Because the birds did so well with the higher quality images, this study could lead to better image-based technology used in cancer screenings.
Although the days of cancer screening results being read by pigeons are a long way off, you may want to pack a few extra bread crumbs in your pocket the next time you visit the park. You could be feeding a future pathologist.