Transcript bioluminescence

Mrs. Evans:Creatures of the Deep
Analysis of Animal Adaptations
Long-nosed Chimaera
Vampire squid
Coffinfish
Giant Isopod
Giant Squid
Gulper Eel
Angler
Dragonfish
Fangtooth
Viper fish
External Fish Anatomy
Types of caudal fin
• Lunate, crescent
• Fast, rapid swimmers
Types of caudal fin
• Round
• Strong swimmer,
slower
Types of caudal fin
• Forked
• Constantly moving
Types of caudal fin
• Truncate
• Strong swimmer,
slower
Types of caudal fin
• Lanceolate (pointed)
or leptocercal (long
whip like)
• Wriggling, weak
swimmer, ribbon-like
body
Types of caudal fin
• Sunfish
• Small or
continuous with
body,
• Weak swimmer
Mouths
Mouth
• Terminal (at the
end of the snout),
symmetrical,
anterior
• Feeds throughout
the water
• Walleye, whale
shark, northern
pike
Mouth
• Angled upward/longer
lower jaw, superior,
dorsal
• Feeds on prey it sees
above it; small fish, or
aquatic insects, often
at surface of water
• smallmouth bass,
Mouth
• Ventral, inferior
(under the head)
Under the
snout/longer upper
jaw
• Feeds off the
bottom Feeds on
prey it sees below it;
usually feeds off the
lake or river bottom
• Ray, hammerhead
Mouth
• Sucker-shaped,
subterminal
• "Vacuums" up food off
the bottom; eats aquatic
insects, vegetation
• Sucker, sturgeon
Mouth
• Strong jaws and welldeveloped teeth
• Feeds on other fish
• Northern pike,
walleye, Viper fish
Mouth
• With barbels
• Feeds off the bottom;
Can sense food in
murky water
• Catfish, bullhead,
stonecat, sturgeon
mouth
• Thin mouth (butterfly
fish) good for getting
small invertebrates
from cracks and
crevices
Eyes
Eyes
• Large
• Feeds by sight
• Coloussal squid,
Vampire Squid
Eyes
• Small
• Likely feeds off the
bottom and relies on
barbels to detect food
• Whale shark
eyes
• Fish looks
forward
• Swims through
water column
• Food it eats is
caught in front of
it
eyes
• Fish is called a
stargazer b/c it has
upward, tubular eyes
• Bottom dweller but
feeds on fish above it
eyes
• Eyes are on the side,
can easily pick up
movement in the
water
• Feeds on fish as it
swims through the
water column and can
see all around its
body; front, back,
upward, downward
Spines
• For protection or to stiffen fins for
swimming
• Stone fish, lion fish, puffer, knight
fish
Body Shape
• Rounder, flat bellied,
depressed (Flattened
from top to bottom)
• Feeds off or rests on the
bottom; less conspicuous
to predators
• Flounder, skates, rays
Body Type
• Oval, fairly long
• Prefers more open
water or a few weeds
• Walleye
Body Shape
• Oval, very long, eel-like
• Fast-moving in quick bursts;
Agile around rocks and weeds,
lie-in-wait predator
• Northern pike, pickerel
• Thin, shorter, discshaped, laterally
compressed
• Agile around
rocks/weeds; round
shape harder for
predators to swallow
• Angel fish
Body Shape
• Torpedo-shaped
(fusiform)
• Stream-lined for high
speed or swimming in
currents
• Tuna, rainbow trout
Body Shape
Scales
• Large
• Used for protection;
speed not needed to
catch food
• Carp, sucker
Scales
• Small or nonexistent
• Fish more
streamlined
and fastmoving to
catch prey
• Agnatha,
Northern pike,
catfish, burbot
Coloration
• Fairly uniform, no
markings
• Swims in open water
Coloration
• Stripes (disruptive
coloration)
– The patterns and lines
break up the outline of the
fish
• Hides in weeds for
protection or to ambush
prey
• Perch
Coloration
• Mottled
• Hides in rocks or on
bottom
• Northern pike, young
sturgeon
Coloration
• Dark on top
• Less visible to
predators above it
• Light colored belly
• Less visible to
predators below it
• shark
Coloration
Coloration
• Eye Spots
(A form of mimicry,
the eye spot draws
attention away from
the head)
Pacific Viperfish
Pacific viperfish
feeds on lanternfish and squid.
It has a very large mouth and fang-like teeth.
Its size ranges from 22-30 cm.
Two rows of photophores.
Look at the long, thin ray on the back (dorsal) fin.
How might the ray help attract a tasty meal?
This squid can grow to 30 cm in length.
Its photophores adjust to match the ocean twilight.
It can move very quickly forward or backward.
The two longest tentacles grab and hold its prey.
The smaller tentacles move the prey to its mouth.
The eyes are of different sizes….Scientists don’t
know why.
Very common in the deepwater.
It lives where there is some light...very large eyes.
Verical migrator.
Photophores
It grows to about 13cm in length.
10 cm in length.
The "lure" is a large photophore. It may
help attract prey.
It is hard to find and keep mates in the deep sea.
They mate for life.
hatchetfish
small (6 cm)
has upward facing eyes.
upward facing mouth can grab its prey.
The hatchetfish has photophores on the bottom
side. The light helps hide its outline. Other fish
swimming below the hatchetfish see the light and
not the hatchetfish's silhouette. …countershading.
The snipe eel grows to 140 cm in length. It is
among the biggest deep sea fish. It has a very
long beak-like mouth. The mouth has bristles
along the edges. For a long time scientists
wondered how the snipe eel used these bristles.
Finally, they observed the snipe eel feeding. The
snipe eel waves its head back and forth in the
water. The bristles act like Velcro to snag deep
sea shrimp by the antennae.
The bright red Deep Sea Shrimp is only 4 cm
long. It seems much longer because of its very
long antennae. These antennae may sense
different chemicals in the water. The chemicals
help the shrimp find food and mates. They may
also help it avoid predators. The Deep Sea
Shrimp has red photophores on its underside.
The photophores countershade the shrimp.
The gulper eel has a very large mouth. It
also has a stomach that can stretch. This
lets the gulper eel eat prey equal to itself
in size. The gulper eel can grow to 76 cm.
Most gulper eels are about 40 cm long.
The dull brown tripod fish lives on the ocean
floor. The pelvic fins are very long, about half the
length of these fish which can grow to 29 cm.
The pelvic fins and long tail help the tripod fish
skim along the ocean floor. Tripod fish eat tiny
animals (zooplankton). Threads on the fins
sense the zooplankton in the water when they
brush into the fins.
The translucent eelpout is a common deep water
fish. It has a very uncommon behavior. When
this fish is startled, it rolls up into a donut shape.
Scientists wonder how this helps them survive.
Some think it makes the eelpout look like a
stinging jellyfish. The eelpout grows to 18 cm. It
eats any animal it can fit into its mouth.
Many different kinds of siphonophores live in the
deep sea. This one can grow to 20 meters in
length. A siphonophore is one animal made of
many individual animals. Scientists call it a
colony. The tentacles act as fishing lures. The
lures attract the prey. The tentacles sting it.
Then they pull it into one of the mouths.
This 4 cm long jelly can glow (bioluminesce). Its
tentacles pulse blue and red. They change color
as it swims through the water. When a predator
appears, the colobonema increases light output.
Then, in an instant, it separates its lighted
tentacles. The jelly swims off in a different
direction. The predator is left with some stringy
tentacles. The jelly is free.
amphipod
blackdragon
bristlemouth
Larvacean
Giant Isopod
(Bathynomus gigateus)
• The giant isopod can grow to a length of
over 16 inches, which makes it one of the
largest members of the crustacean family.
Divisions of the Deep-sea Habitat
• Mesopelagic: from 200 m to 1000 m, near the
margin of the continental shelf. Known as
• the disphotic zone because it represents the
lower limit of photosynthesis.
• Bathypelagic: from 1000 m to 4000 m. Known
as the aphotic zone because no surface light
• penetrates to these depths.
• Abyssopelagic: the pelagic zone below 4,000
m.
Physical Parameters of the Deep
Sea
• Describe how the deep-sea environment
differs from shallow habitats in terms of
light
• levels, organic production, temperature,
and pressure.
•
What are the major sources of nutrient
input into the deep sea?
Feeding in the Deep Sea
• There are two main feeding strategies
utilized by deep-sea fishes, each with its
own set of
• morphological adaptations:
• 1). Opportunistic Carnivory: Food is rare in the
deep sea, so many fishes just eat
• whatever they can catch, whenever they can
catch it. Morphological adaptations may include
• expandable stomachs, disconnected pectoral
girdle (expands gape), large fangs,
• bioluminescent organs, and elongate bodies
with posterior fin placement.
• 2). Benthic specialization: When food hits the
bottom, it stops. As a result, many
• fishes specialize in food resources that can be
found on or near the sea floor. Scavengers
• dominate, but filter feeders and carnivores are
also common. Morphological adaptations
• may include well-developed lateral line and
olfactory senses, caudal and pectoral fin
• modifications, and elongate tapered bodies.
Physiology of Deep-sea Fishes
• Metabolism: Cold temperatures and lack
of nutrients result in slow metabolic rates.
Mesopelagic
• fishes are slow and lethargic, which is an
energy-saving strategy. Much of the
movement is vertical.
Sensory Systems
• Vision: In the mesopelagic environment light levels are
low, so adaptations to enhance the lightgathering
• capabilities of eyes are common, as are bioluminescent
organs. The eyes of mesopelagic
• fishes may be very large or tubular, and may possess a
tapetum lucidum. In the bathypelagic,
• abyssopelagic and deep benthic zones light is
completely absent. The eyes of fishes in these habitats
• may be extremely reduced or lost.
• Olfaction: In the mesopelagic and bathypelagic
zones olfaction appears not to be very important.
• Olfactory systems are generally not well
developed, except in species which find mates
by smell. In
• contrast, fishes associated with the sea floor
tend to have very well developed olfactory
organs,
• which may be used in foraging and reproduction.
Adaptive Morphology
• Organisms that live in
the dep sea have to
adapt to the various
conditions they find
there. The shape and
structure of the body
of deep sea creatures
is adapted to those
conditions.
Scarce food affects body structure
• b/c food is scarce,
deep sea fish tend to
conserve as much
energy as possible.
The energy they have
must be allocated
between growth,
maintenance and
reproduction.
Deep sea fish lower their energy
use by…
• having weak
muscles
• bones that are less
dense
• lower metabolic rate
• slower breathing
rate (respiration)
• very reduced swim
bladder
Adaptations for feeding
• Deep sea fish need to
take full advantage of
any potential prey
they might encounter
so they tend to have
large mouth, jaws and
teeth and highly
extendible stomachs
so they can handle
large prey or carcass.
This fish can extend its stomach up
to three times its size swallowing
much bigger prey.
Adaptations of the lateral line
• The lateral line in fish is used
to detect movement around
them. It consists of
neuromasts, mechanosensory
cells with cilia (hairs) that can
detect water displacement and
therefore movement. Because
the upper ocean has currents,
the detection system is located
in closed or open pits. In the
deep sea, fish do not need to
worry about strong currents
therefore their lateral line is
located on the surface or even
on stalks.
Body size in deep sea fish
• In early studies of
demersal deep sea fish,
increasing body size
was been reported and
this became known as
the Heincke’s Law. Later
studies however appear
conflicting with increases
or decreases in body
size with increasing
depth reported. The
differing trends between
different groups of deep
sea fauna may be due to
their behavior and
ecology.
• scavangers have an
increase in body size
with depth whereas
predators less so or
even a decrease in
body size with depth
• Visible light made by
living creatures is
known as
bioluminescence.
• bioluminescence the emission of visible
light made by living
organisms such as
the firefly and various
fish, fungi, and
bacteria.
• the firefly is probably
the best recognized
example of
bioluminescence
many organisms in
each kingdom exhibit
it as well
• bacteria, protozoa,
fungi, sponges,
crustaceans, insects,
fish, squid, jellyfish,
and lower plants.
On land, bioluminescence is rare.
• By contrast, in the
oceans,
bioluminescence is
very, very common. In
fact, it would be
difficult to find any
place in the ocean
where
bioluminescence
doesn't exist.
Flashlight fish
• In the mesopelagic
zone (200-1000 m),
approximately 90% of
all the animals (fish,
shrimp, squid, and
gelatinous
zooplankton) are
bioluminescent.
• Light is generated either by the
fish itself or from light emitting
bacterial cells.
Bioluminescence is created
from an enzyme called
luciferase, which is activated
by oxygen (thereby enabling a
regulatory control mechanism).
It is of interest to note that
bioluminescence only occurs
in salt water fish as salt is also
one of the necessary elements
for bioluminescence.
•
•
The light is produced by symbiotic
bacteria within light-emitting cells
called photophores. It is produced by a
chemical reaction when a substance
called a luciferin is oxidized. When the
light is released, the luciferin becomes
inactive until it is replaced by the
animal. Some animals can make
luciferin themselves, or it may be
synthesised by symbiotic bacteria
inside the photophore.
The photophores, or light-emitting
cells, range from simple clusters of
cells to complex organs surrounded by
reflectors, lenses, colour filters and
muscles. The most common coloured
light produced by marine organisms is
blue. This is also the colour that
penetrates furthest through water.
The vampire squid lives in very deep
waters around the world. This small
squid has glowing tips on its tentacles.
• One of the features of
biological light that
distinguishes it from
other forms of light is
that it is cold light.
Unlike the light of a
candle, a lightbulb, a
star or even the glow
of heated metals,
bioluminescent light is
produced with very
little heat radiation.
• Were it not for
bioluminescence it is
probable that most
deepsea fish would
be blind.
Bioluminescense
therefore serves a
mulitude of functions increased vision in
otherwise lightless
environment, attract a
mate, seek out or lure
prey closer, frighten
off potential attackers
and most importantly
camoflage.
"A flash of light in the ocean is a
big deal and all eyes are drawn
to it"
• Most deep-sea fish have large eyes to
gather as much of that light as possible.
The crucial feature for capturing photons is
the size of the pupil, and for some fish the
only way to enlarge the pupil without
making the eyes too big to fit in the head is
to do away with the outer parts of the
eyeball.
• The Flashlight fish of
the Red Sea uses
bioluminescence to
see better in the dark
sea environment it
inhabits.
The light that shines
from pockets under its
eyes act as
headlights for the fish
as it swims about.
• Like most bioluminescent
fish, it does not produce its
own light but instead
harbours bioluminescent
bacteria. The bacteria living
in this pocket under the eye
are always producing light,
so this fish has a flap of
skin like an extra eye lid to
cover the lighted pocket
when it doesn't want to be
seen.
• This symbiotic relationship between fish
and bacteria can be used by the fish to
help in sight as in the case of this fish, to
help keep schools together by making the
individual fish easier to see, to make a
quick escape from predators by leaving
behind a cloud of light, or to hunt.
Attraction of Prey
• The Angler fish is an
example of a fish that
uses its symbiotic
bacteria to make
hunting easier. The
lighted spot on the
end of a rod sticking
out of the fishes head
is used as a lure.
When other fish come
close to see what the
light source is, they
are easily snapped up
by the angler's jaws.
Interspecies Recognition
• Dragonfish have two sets of light organs
on their heads.
A pair of photophores (light emitting
organs) located behind the eye emit bluegreen light, like other fish. A second light
organ beneath the eye emits light in the
red part of the spectrum, which is invisible
to other fish.
• Although the red light
doesn't travel very far,
it allows the
Dragonfish to see
their prey without
alerting the prey or
any potentially
curious predators;
plus it also enables
this species to signal
each other using the
red light and as such
it becomes a visual
signalling system that
is only meant for
themselves to see.
Camoflage
• In an effort to try and blend into
the environment species emit
light of a similar wavelength to
ambient light levels, thereby
disguising the shadowing
silhoutte their bodies cause
when perceived against an
illuminated background. The
use of ventral and lateral
bioluminescent photophores
enables 'countershading'
camoflage.
• ventral - describes the lower
abdominal region of an
organism
• lateral - is relating to the sides
of an organism of structures
• Even in the twilight zone, dimly
lit by the last vestiges of
sunlight, bioluminescence
comes in handy. An animal
looking upwards will see the
shadowy silhouettes of
creatures moving overhead
against the dim light above.
Some fish and squid make
themselves invisible by
counterillumination, giving out
light of matching intensity from
photophores along their
bellies.
• The Hatchet Fish live and hide
in the down welling sunlight of
the Mesopelagic zone (2001000m) by the use of
bioluminescence.
The Hatchet Fish has little
"holes" or clusters of ventral
photophores and the light
emitted by these photophores
in conjunction with the odd
body features eliminate the
fishes silhouette thus providing
an effective means of evading
predators.
Deep-sea cucumber
Snaggletooth
Deep-Sea Lizardfish
Deep-sea glass squid
Fangtooth
This deep sea shrimp,
Acanthephyra purpurea, spews
bioluminescence to blind or distract
a predator.