Yes. The Chihuahua is made from off-the-shelf components though. I believe the aliens would have broken it down even further, experimenting on a fundamental level hundreds of millions of years ago.
According to some abductee interviews, the aliens are tired of this particular petri dish, regarding it as a complete failure, and are extracting DNA to make hybrids for some Earth 2.0, elsewhere in the galaxy. Kinda like Clarke's "Childhood's End".
IOW - "Thanks for playing, you can keep the planet, have a nice eon.
P.S. watch out for asteroids"
Fun stuff.