196779
Fossilized Ectocion jaw bones show that this genus was smaller during ( E. parvus , 55.5 mya ) the PETM than its relatives before ( E. osbornianus , 55.6 mya ) and after ( E. osbornianus , 55.3 mya ) the brief climatic peak period .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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