Obviously domestic cats are not bipedal. They are quadrupedal meaning four-footed; they walk on all four feet. However, we often see domestic cats taking up these positions but not quite in such a relaxed or interesting way as we see in the photographs. I selected the photographs because they are particularly good examples of bipedal domestic cats although they are static probably and therefore not, strictly speaking, bipedal. It just makes a good title. I also call this position the meerkat position because we see meerkat typically taking up this stance. Both the domestic cat and the meerkat take up this stance in order to see better. Their head is elevated and therefore they can see over obstacles. Update: I have added a sixth: a lion cut grey Persian.
It shows an intent to observe something. We also see domestic and stray cats taking up this position when they are in an antagonistic interaction with another cat possibly over ownership of terrain. It’s rare to see this under the circumstances where territory is being defended but the objective is to look taller and therefore more dangerous. We know that domestic cats also take up various other positions to look more intimidating such as the sideways-on position and the “crab walk” together with erect hair strands. They all add up to looking bigger and scary. Occasionally, stray and domestic cats do actually walk on their hind legs under extreme circumstances in which case they are genuinely, temporarily, bipedal.
Some more on cat gait
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