Sonar Defences

[thedanster7000]

I'm making a bat/bear/ankylosaurus hybrid that uses Sonar to 'see'. Does this advantage include 360 Vision? I'd assume so but it doesn't specify.

Thanks in advance.

[Kalzazz]

Bats ears seem more focused forward so I wouldn't assume so

[Dalin]

I'd need to do some research, but I wouldn't assume that sonar is omnidirectional. For bats, I'm pretty sure it is highly focused. Not as sure about dolphins in the water, but bats are a better model for your example. I would add 360° Vision as an additional feature if that's how you want it to work.

[Kalzazz]

I was curious, so I Googled it

https://news.nationalgeographic.com/...ic-navigation/

This article sells me that bats do have 360 degree echolocation

[thedanster7000]

I've gone with 360 Vision separately just in case. Here's what I ended up with if anyone's interested:


Batbeast

---
A bear-sized monstrosity with a mutated head resembling that of a bat. Its legs are thick but cumbersome, and too awkward to use to swipe. Veins bulge from its black, hairless body and huge ears sprout from its head, which it uses to navigate in place of its missing eyes. Most notably, a long, slender, and muscled tail sports a huge mace-like end, resembling that of an Ankylosaurus.
They stay dormant until prey comes within range of their sonar, at which point they use their massive tails to incapacitate their victims before ripping into them with their many layers of razor sharp teeth.
---

ST: 18
DX: 12
IQ: 5
HT: 12

HP: 18
WILL: 11
PER: 12
FP: 12

SPEED: 6.00
MOVE: 7

SM: +1
DR: 1

DODGE: 10

BITE (13): 1d+1 cutting. Reach C.
TAIL (13): 2d crushing. Reach C,1.

TRAITS: 360 Vision; Combat Reflexes; No Eyes; Quadruped; Silence 1; Sonar (30 yards); Wild Animal.

SKILLS: Brawling-13; Stealth-12.

CLASS: Dire Animal.

[Kalzazz]

Nifty monster, I will have to steal

[Dalin]

Originally Posted by Kalzazz

I was curious, so I Googled it

https://news.nationalgeographic.com/...ic-navigation/

This article sells me that bats do have 360 degree echolocation

[NERD]

Now I'm intrigued! The article clearly says that "echolocation can provide information from 360 degrees around." That seems conclusive but is potentially at odds with another study of the same bat species, Echolocating bats emit a highly directional sonar sound beam in the field. Here's a tidbit from the conclusion that's interesting:

Bat echolocation frequency is assumed to be a compromise between resolution and range, because only at high frequencies (short wavelengths) will small insects be efficient echo reflectors (Møhl 1988), while at the same time atmospheric attenuation is also more severe as the frequency increases. However, the range reduction by increased atmospheric attenuation is offset by the increased directionality at higher frequencies, which focus more sound energy in the forward direction. This implies that the cost of increasing the frequency may not be the range, but rather the width, of the sonar, or the bat's ‘peripheral vision’.

I don't have enough time to drill down further right now, but I wonder if bats have multiple echolocation modes? The article implies that they send their signals from their mouths, so maybe they can twist their heads around and fire their beams in multiple directions. But that's not quite the same as the 360° Vision advantage.

[/NERD]

Regardless, I wouldn't care about any of this in the game. Batbeasts with 360° Vision sound awesome!

[Anthony]

In Basic, scanning sense has a 120° arc unless you enhance it. In DF, I would assume that any esoteric senses work like vision unless specified otherwise.

[ArchonShiva]

Note that Peripheral Vision does provide information from 360 degrees around. You get less information about what’s right behind you, but you don’t effectively have any blind spot. This seems much more appropriate for an animal with a front and back than 360 vision, which is intended for beholders and sentient mushrooms.

[Flyndaran]

Bats' area of sharp "vision" is negatively correlated with resolution. The higher the frequency, the shorter the range, sharper the focus, and narrower the field of view. That's also why some go upward of 120 dB. They are much louder than they seem.
Even at sharpest their resolution absolutely sucks compared to human.

Of course none of that matters for gaming or fiction.