Transcript Bellwork – 1/27/2014

Bellwork – 1/27/2014
1) What are some reasons for male aggression?
2) How is imprinting different than conditioning?
**Exam on Wednesday!
Reproductive behavior
• Sexual selection
– Courtship/Dominance – hooded seal, bird
of paradise
– Female choice
– Male aggression
• Leks – a gathering of males for the purpose
of competitive mating displays.
http://www.youtube.com/watch?v=uGIQxBbYm10
http://www.youtube.com/watch?v=r3-Q3x3j6zw&feature=related
Mating strategies
• Why are females, biologically, more important
than males?
• Human Examples:
– Mrs. Feodor Vassilyev – 27 births, 69 children (16
pairs of twins, 7 triplets, 4 quadruplets) [1707-1782]
– Ismail Ibn Sharif – 867 children (525 sons, 342
daughters) [1672-1727]
Mating strategies
• Promiscuous
• Monogamous
• Polygamous:
– Polygynous – many females (anything with an
alpha male, lions, hippos, many primates)
– polyandrous – many males (pipefish,
honeybees, blue whales)
• Certainty of paternity matters!
Kelp Greenling
Multiple paternity – broods of half brothers & sisters
Symbiosis
Hippocampus barbiganti
Pigmy seahorse
Symbiosis
Trumpetfish / herbivores
Clownfishes / Anemones
Vendellia cirrhosa (The dreaded Candiru)
Urinophilus diabolicus (leach-like)
Behavioral ecology
• Animals behave in ways that maximize their fitness
– Reproductive behavior = more successful offspring
– Feeding behavior = maximum energy gain
• Research examples:
– Sparrows and cuckoldry
– Cheetahs and prey selection
– Elephant seals and polygyny
– Humpback whale songs
Feeding Behavior
• Example - Sunfish, provide predator with
prey of different sizes and different
densities, fish respond by foraging
optimally (taking the most energetically rich
prey under the appropriate conditions)
Feeding Behavior
• Example - Sunfish, provide predator with
prey of different sizes and different
densities, fish respond by foraging
optimally (taking the most energetically rich
prey under the appropriate conditions)
Fish Behaviors
• Migration
• Shoaling (schooling/swarming)
• Feeding
• Aggression
• Resting
• Communication
Fish Migration
• Fish migrations are usually round-trip
• Reasons for migration
– Food gathering
– Temperature adjustment
– Breeding
Timing of migrations
– Annual
– Daily
– generational
Classification of Fish Migration
•
Diadromous – Travel between sea & fresh water
– Anadromous – most of life at sea, breed in fresh water
– Catadromous – most of life in fresh water, breed at sea
Reasons for Migrations
• Take advantage of different habitats
– Feeding
– Protection
• Avoid adverse conditions
• Meet requirements for reproduction
Orientation During Migration
• Orientation to gradients of temperature,
salinity, and chemicals
• Orientation by the sun
• Orientation to geomagnetic and
geoelectric fields
Disadvantages of Migrations
• Expenditure of energy
– Most must store energy before migration
• Risk from predation
Adjustments Required Due to
Migrations
• Adjusting physiologically to new water
conditions
– Temperature
– Light
– Water chemistry
• Many migratory species are now rapidly
declining due to changes caused by man
Migration
Migration
10,000 Golden Rays migrating from Florida to Mexico
Get into groups of 2
1) Give three examples of animal migration. Why do
they do this? Where do they go?
2) Why would it be beneficial for a species to learn to
always take down the largest available prey? The
weakest prey?
3) How is a fixed action pattern different than learning?
4) Which has a greater influence on an aquatic species,
nature, nurture, or somewhere in the middle. Provide
an argument with examples.
5) Is there a reproductive strategy that is MOST
advantageous? Describe a situation in which each of
the following could be ideal: monogamy, polygyny,
polyandry
Bellwork – 1/14/2013
1) All things being equal, a hunter will go for which
type of prey?
2) How is a catadromous migration different than an
anadromous migration?
Definitions
• Shoal - any group of fishes that remains
together for social reasons
• School - a polarized, synchronized shoal
(has coordinated, directed movements)
How do Schools Work?
• Requires great deal of coordination among
individuals in the school
• Vision is primary sensory cue for
coordinating movement
• Use of optomotor reaction - individual
movement is coordinated with movement of
some other visually distinctive object - e.g.
a spot or a stripe
Functions of Schooling Behavior
• Hydrodynamic efficiency
– individuals obtain reduction in drag by
following in “slip-stream” of neighbors
– limited evidence in support of this
Functions of Schooling Behavior
• Reduced predation risk
– creates patchy distribution of prey - large areas
with no prey
– once school is found, individual risk of being
captured is reduced by dilution
– confusion of predators by protean displays,
encirclement, other behaviors
Functions of Schooling Behavior
• Feeding
– increases effective search space for the
individual (more eyes, separated by greater
distance)
– coordinated movements to help break up
schools of prey - analogous to pack behavior in
wolves - by tunas, jacks
Functions of Schooling Behavior
• Reproduction
– increases likelihood of finding a mate
– facilitates coordination of preparedness
(behavioral and pheromonal cues)
– facilitates arriving at right spawning site at right
time
Fish Behavior & Communication
• Shoaling
• A social grouping of fish
• Occurs throughout life in about 25% of fish
species
• Half of all fish shoal at some time
• Benefits of Shoaling
• Gives a predator many moving targets
– Confuses predators
– Increases chances at the individual level
– Increases food finding ability
• Keeps potential mates in close proximity
Fish Behavior & Communication
• Pods
• Tightly grouped school
• Move as a single unit (including making
quick turns)
• Makes the pod appear like one large
organism
– Protection from predators
Liabilities of Grouping Behavior
• Increased likelihood of disease & parasite
transmission
• Becoming more conspicuous to some
predators
– Harvested more easily by man
Feeding Behavior
• Morphology is often a key to feeding behavior –
many fish have specialized habits
• Actual feeding may depend on what is available
• Optimal foraging – Take whatever is closest, as
long as it is suitable food
– Highest quality of food for the least amount of
effort
Optimal Foraging
• All else being equal, take the largest prey
• Don’t choose prey that takes more energy
than it provides
• Be in a habitat that provides the type of
food you are looking for
Risk Sensitive Foraging
• Foraging is sometimes restricted because of
undo risk
– It does not make sense to look for prey
where you will become the prey
– Must balance energy gain possibility with
risk of obtaining the energy
Aggressive Behavior
• Direct charges
– Often includes biting
- Ritualistic displays
– Modified swimming
– Flaring gill covers
– Color changes
– Threatening movements
Reasons for Aggressive Behavior
• Defense of territory
– Usually connected with reproduction
– Sometimes to keep food source
• Defense of brood
• Repelling competitors for mates
Resting Behavior
• Inactive state
• Some fish spend a large part of the day not
doing anything
• Many species change color patterns
• Most fish rest on or near the substrate
• Many fish have a specified time of day
when resting takes place
• Some fish never rest (Sleep swimming?)
– Must keep moving (sharks)
How visual signals are produced
• Types of coloring
– Pigments
• Colored compounds
• Located in chromatophores
– In mostly in skin, but also in eyes &
organs
• Controlled by hormones & nerves
Red Coloration
• Red fish are common
• Cryptic color in low light
• Blends in to red algae
• Used in spawning fish
– Recognized at short distances
– Does not attract predators at long distance
• Bright, complex color patterns
– Some fish use this to advertise when
protecting territories
– May serve to signal shoal
– In some cases it may be used for predator
avoidance
• Blending into a complex background
– Flash effect to avoid predators
– May serve as a warning to others
• Disrupt the outline of the fish
– Make them less visible
– Often associated with beds of plants
Also known as “protective resemblance” or
“aggressive resemblance”...depends on
state of animal.
Oriental Sweetlips
Leafy Sea Dragon
Coleman Shrimp
Toadfish
Leaf Scorpionfish
Flounder
• Being dark on top, light on bottom
– Look like substrate from above
– Look like water surface from below
Eye Spots
• Usually at base of caudal fin
– Usually used to confuse predators
• Common in some fry
– Sometimes used for species recognition
Lateral/Horizontal Stripes
• Mid-lateral band usually
• Best developed in schooling fish
– Keep school oriented while
confusing predators
– Makes it hard to pick out individuals
Emperor Angelfish
Sergeant Major
Copperband Butterfly
Auditory Signals
• Most fish produce sounds
• Uses for sound
– Courtship singing
– Territorial defense
– Signaling shoal
Sound Production
• Stridulation
– Rubbing hard surfaces together
– Low frequency sounds
• Vibration of swimbladder
– Can give loud croaking
•
Photo used with permission of Dr. Craig S. Kasper