http://news.liv.ac.uk/2014/07/18/using-big-data-approach-to-map-relationships-between-human-and-animal-diseases
Some sci-fi movies depict monstrous organisms that absorb or Mimic humans and animals. Perhaps even their diseases, which can still be used against other organisms.
http://ca.ign.com/wikis/prometheus/The_Black_Substance
Instead of using millions of fighters for an invasion force, a special genetically modified organism can merge & rapidly mutate with the various life forms on a planet.
http://avp.wikia.com/wiki/Chemical_A0-3959X.91_%E2%80%93_15
Quite a monstrous shit-mix to take over various worlds, indeed.
http://dnaresearch.oxfordjournals.org
http://en.wikipedia.org/wiki/The_Island_of_Doctor_Moreau 1896 book
https://www.youtube.com/watch?v=QT1oPQLEi_M,
http://en.wikipedia.org/wiki/The_Island_of_Dr._Moreau_(1977_film)#Production,
http://en.wikipedia.org/wiki/The_Island_of_Dr._Moreau_(1996_film)#Plot
http://en.wikipedia.org/wiki/Splice_(film) ,
https://www.youtube.com/watch?v=8pIeSYhipUs,
https://www.youtube.com/watch?v=9BkKijD3Wfw
http://hmg.oxfordjournals.org
http://www.wired.com/2012/06/prometheus-science-faith-creationism,
http://en.wikipedia.org/wiki/Prometheus_(2012_film)#Sequel,
http://www.scified.com/site/prometheusmovies/ridley-scott-currently-scouting-filming-locations-for-prometheus-2-in-australia,
http://www.prometheus2-movie.com
Worms & Snakes:
http://news.liv.ac.uk/2014/07/17/worm-study-provides-hope-for-deadly-disease-of-the-brain/
http://monstersandbeasts.blogspot.ca/2012/06/prometheus-worm.html
http://monstersandbeasts.blogspot.ca/2011/03/carnictis-sordicus-vile-meat-weasel.html,
https://www.youtube.com/watch?v=DTWYQhTT388
http://monstersandbeasts.blogspot.ca/2011/10/thing-2011-monster-forms-ll-be-updated.html,
http://monstersandbeasts.blogspot.ca/2011/03/thing.html
http://monstersandbeasts.blogspot.ca/search/label/bio-recombinators
http://monstersandbeasts.blogspot.ca/search/label/Octopus%20Monsters,
https://www.youtube.com/watch?v=os6HD-sCRn8
Squids
https://www.youtube.com/watch?v=v_uU8PaqJ9g
Spiders
https://www.youtube.com/watch?v=yWy0cuxNWDw