are they related to any other species?
The most common natural predator of sperm whales is the killer whale, but pilot whales and false killer whales sometimes harass them.
Sperm whale
The most common natural predator of sperm whales is the killer whale, but pilot whales and false killer whales sometimes harass them. Killer whales prey on target groups of females with young, usually making an effort to extract and kill a calf. 
what group of animals do octopus belong to Molluscs how big do they grow? Adults usually weigh around 15 kg (33 lb), with an arm span of up to 4.3 m (14 ft). how many limbs do they have? Eight what is the largest of its kind? The giant Pacific octopus where is this type normally found? The coastal North Pacific, along California, Oregon, Washington, British Columbia, Alaska, Russia, Japan, and Korean Peninsula. what does it feed on? Shrimp, crabs, scallop, abalone etc. how long do they normally live? Typically 3–5 years in the wild. what is a threat that it faces? Scavengers and other organisms often attempt to eat octopus eggs; preyed upon by many other zooplankton and filter feeders, harbor seals, sea otters, and sperm whales. what toxic material does it have? High concentrations of heavy metals and PCBs where are the above mentioned seals found? Found along temperate and Arctic marine coastlines of the Northern Hemisphere. what do they look like? Possess a unique pattern of spots, either dark on a light background or light on a dark; vary in color from brownish black to tan or grey; body and flippers are short, heads are rounded; nostrils appear distinctively V-shaped. what are the overall numbers of them? There are an estimated 350,000–500,000 harbor seals worldwide. can you describe the earlier mentioned whale? At birth both sexes are about the same size, but mature males are typically 30% to 50% longer and three times as massive as females. where does its name come from? It is a truncation of "spermaceti whale".
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Sperm whale [SEP] Relations with other species
The most common natural predator of sperm whales is the killer whale, but pilot whales and false killer whales sometimes harass them. Killer whales prey on target groups of females with young, usually making an effort to extract and kill a calf. The adults will protect their calves or an injured adult by encircling them. They may face inwards with their tails out (the 'marguerite formation', named after the flower). The heavy and powerful tail of an adult whale is potentially capable of delivering lethal blows. Alternatively, they may face outwards (the 'heads-out formation'). Other than sperm whales, southern right whales had been observed to perform similar formations.