In taxonomical terms, what family of animals has the broadest range of size?

I would guess mammals. You have mammals that are no bigger than a human finger and then there’s the great blue whale which is way more than 33 times the size of one of those mammals.

I have no idea. Cats come in lots of sizes.

Point of order:

@KatawaGrey, mammals are a class, two levels above family.

Hmm, perhaps dolphins? The smallest is the 30lb Maui, the largest the 12,00lb orca.

Or the dwarf sperm whale at 300lbs versus the blue whale at 150 tons.

I have no idea. Now, I’m researching like a fiend.

Kingdom, Phylum, Class, Order, Family, Genus, Species.

Mammal=Class

Ah, asmonet, you changed your answer and now I look like I’m picking on Katawagrey. And in hindsight, I think I have my whales categorized too broadly, but the dolphin stills works.

Pythonidae?

“Adults range in size from 0.5 to 10 meters (1.5 to 33 feet) in length.”

Funny, similar ratio to your frog.

Whales, I would think. The smallest is the dolphin, right up to the enormous blue whale.

Reaction upon seeing the Brazilian Gold Frog:
Aww, what a cute little thing.

Reaction upon seeing the Goliath Frog:
OH GOD, KILL IT WITH FIRE!

Everyone seems to forget that invertebrates are animals. I would think that squids could weigh in on the size thing. But, I’m not an invertebrate guy, so I can’t name off any families.

I went off steve’s tip, and dug up…

Cranchiidae, the glass squids. They can range from the Cranchia at 150 mm to the Colossal Squid, at 14 meters. That is a ratio of 93.3. [Edit: that ratio only applies to length. If we were talking weight, it’d probably be a ratio of tens of thousands.]

And it appears to be the family to beat!

@robmandu: oh, I thought you meant just generic group of animals. Well, I am a communications major so I don’t need to remember all this science stuff…

@tonedef: zesty!

@steve, I want someone to challenge it! I’m sure there’s something bigger. I had to dig a little bit, because the giant squid is in its own family, architeuthidae.

In the Fluther spirit, I tried to find a jelly competitor, but the family of the Lion’s Mane Jelly is rather limited.

Based on @syz’s numbers, the weight ratio between the blue and dwarf sperm whales is 1000:1.

But then Wikipedia says that a blue whale can size up to 200 tons. And the dwarf sperm whale weighs in at 551 pounds. Yielding a weight ratio of 725:1.

The largest colossal squid on record weighed in at 1,091 pounds. So, to beat the whales’ ratio, then we need to find out if the glass squid weighs in at less than 1.5 pounds. At only 15cm long, I’m sure it’s only a fraction of that… but so far can’t seem to find a citable reference. :-\

—

This is fun, thanks all!

I think that this will be difficult to calculate, and you’ll know why when you take a look at the little squid. It’s practically a ball of water. A flaw in this question was that we didn’t set a standard for how to measure size.

Hey! News flash: The dwarf sperm whale is not in the same family as the blue whale. The pygmy sperm whale is a member of Kogiidae, which only has one other species in it, the pygmy sperm whale. It’s not even in the same family as the regular sperm whale. In balenopteridae (the rorqual family, which includes blue whales), the smallest species is the Northern Minke Whale which reaches 9 tons.

The squids rule the day! They take on all challengers!

Geez, I don’t know why I am so invested in this question. It’s so exciting! I love hunting on wikipedia. More like this plz.

Ah, please note, I did later retract my whale theory, although I haven’t looked for size disparities within whale families (too lazy at the moment).

The dolphins do work out to 400:1 (I had a typo on the wight of the orca, it’s 12,000).

Dolphins are whales, remember.

Tenrecidae has the largest range percentage-wise of any mammal family as far as I know.

Delphinidae has a range from the adorable Heaviside’s Dolphin (1.8 m, 75 kg) to the Orca (largest ever was 9.8 m, 8 tons [presumably metric tons]). That’s… weight: 106.6, length: 5.4. Impressive, and it’s the most promising mammal family so far, but still not the winner.

I’ve looked up some other likely families and come up short: anacondas are fail, sunfish are fail, whale sharks are fail, tapeworms are fail. The Praya Dubia was promising, but I think it’s alone in its family.

We might have a winner in Octopodidae. Smallest: Enteroctopus micropyrsus (2 cm) and North Pacific Giant Octopus, at 4.3 m, for a length ratio of 215. Looks like the ‘pi are the ones to beat.