Answer : No, a Porpoise is not heavier than an Alpaca
The average weight of a Porpoise is 53 kg, (117 lbs) versus 65 kg, (143 lbs) for an Alpaca 
 
| Name | Name:Porpoise | Name:Alpaca | 
| Weight | Weight:53 kg, (117 lbs) | Weight:65 kg, (143 lbs) | 
|  | * Harbor Porpoise - ranges from 45 to 60kg | * ranges from 48 to 84kg | 
| Height | Height:n/a | Height:95 cm, (3 ft, 1.4 in ) | 
| Top Speed | Top Speed:23 kph, (14 mph) | Top Speed:n/a | 
| Lifespan in Wild (years) | Lifespan in Wild (years):15 | Lifespan in Wild (years):23 | 
| Description | Description:Harbor Porpoise are among the smallest cetaceans in the ocean. It has small flippers and lives inshore, so is the best-studied of the cetaceans. Their loud puffing sounds make them easy to find. | Description:Alpacas look somewhat like small llammas. They are domesticated animals, bred for their fibers. They are native to South America. | 
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