Camouflage, Chromatophores, bioluminescence

Different light frequencies make it to different _____

heights

Which light color goes deepest? stops shallowest?

Blue goes deepest (high energy)

Red stops highest up (low energy)

Coloration can serve which purposes

• Camoflauge (young salmon)

• Social cue (old salmon, Stoplight parrot fish)

what is the goal of camo?

To blend into surroundings by breaking up identifiable shapes or mimicking surrounding environment, can be color or texture.

How do predators use camo?

To ambush prey

How do prey use camo?

to evade predators

What type of fish are usually considered experts at camo?

Flat Fish

T/F: Many animals that utilize camo try to blend in with the behavior of what they are blending in with

True

Many animals with camo make associations with ____ and make _____ to match

Coral, Pigments

What is integument?

external coloration

What are the layers of fish skin?

Epidermis → Scale → Guanine → Dermis

What does the epidermis have?

Mucus glands, some of the coloration capacity

Where does most coloration occur?

Dermis

what are the 3 cell types that affect color? How do they do this?

• Chromatophores - Reflect Light

• Iridophores - Refract Light

• Photophores - Emit Light

Chromatophores are usually in this shape

Dendritic (Branched)

What determines chromatophore color intensity?

Whether the pigment is aggregated (less intense) or dispersed (more intense)

T/F: Chromatophores do not have the ability to change color

False: They do have the ability to do so

Chromatophores at the dermal level often exhibit camouflage at this dimensional level

2D, parallel to surface

Chromatophores at the epidermal level often exhibit this dimensional level of camouflage

3D (Texture)

Flounders are excellent at changing color to match their environment, how does this happen?

Cognitive process

Name all the relevant pigments, their cell type, and the color that they are associated with

• Melanin - Melanophore - Blacks and Browns

• Carotenoids, Pteridines - Xanthophore - Yellow, Orange

• Carotenoids, Pteridines - Erythrophore - Red, Orange, Yellow

• Unknown - Cyanophore - Blue

• Purine, Uric Acid - Leukophores - Whitish

• Purine Platelets - Iridophores - Iridescence

How do iridophores produce a prismatic effect?

They utilize guanine platelets in the cytoplasm to reflect light

What is the range of iridophore reflection

Prismatic effect → Mirror like

How do iridophores change the intensity or color of their refraction?

Platelets may inflate, deflate

What is countershading?

When fish have a light colored bottom and dark top to be harder to see from above or below

T/F: Bacterial light production involves photophores

False

How specific is bacterial light production?

Species level

Can bacterial light production be “Turned off”

No, but it can be physically shuttered

How many light-producing bacteria/cm³ exist in fish with bacterial light production

10¹⁰/cm³

What is chemical light production?

Photophore based light controlled by innervation

How is color produced from chemical light production

a lens

what is a strong example of a fish that uses chemical light production?

hatchet fish - they have a light organ running across a pipe that is shined into refractive members

What is a predator focused example of the deep sea arms race?

Some dep sea fish are able to see red colored fish by emitting a red light

What is a prey focused example of the deep sea

Some shrimp eject a glowing ink onto predators to expose them