Selfish Shellfish Cells Cause Contagious Clam Cancer

In the 1970s, scientists noticed that soft-shell clams along the east coast of North America were dying from a strange type of cancer. Their blood, which was typically clear, would fill with so many cells that it would turn milky. The rogue cells clogged and infiltrated the clams’ organs, often killing them. This cancer—this clam leukaemia—seemed to be transmissible...

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