This is scrapped concept art for Jurassic Park 4. Its obvious the artist has a wonderful understanding of the figure-the gestures, musculature, and proportions all give an impression of humanity with varying amounts of dinosaur spliced in.
While its easy to mix animal and human features together, a skilled artist can use their knowledge of human anatomy to add personality to an interesting visual. For example: the two characters on the upper right and left each give a different "read" based on pose. Regardless of head shape, the one on the left reads more animal-like based on the position of the arms, that is not a typical pose a human would hold. In contrast the righthand character holds a gesture that looks natural and humanlike. Try sketching the two characters in each other poses-study how the gesture gives a feel of personality in spite of appearance.
