Figure 1

Population biology of invasive species and metastasis. The generalized steps necessary for a species to invade a new ecologic niche are directly analogous to the steps of cancer metastasis (modified from Sakai and colleagues [4]). The transport, establishment, and spread of invasive species can be compared to the intravasation of cancer cells into the blood stream where they are transported to a target organ where they extravasate. The cancer cells then enter a dormant period (lag period for invasive species) before growing, and displacing the host cells (native species). This results in damage to the local organ and eventually the host patient (human impact).