Behavioral Neuroscience (Bats and Electric Fish) Flashcards
Two main bat groups (chiroptera)
Microchiroptera (microbats)
Megachiroptera (megabats)
Two types of formes
Pteropodiformes
Vespetillioniformes
From the two groups which is capable of laryngeal echolocation?
Microchiroptera (yangochiroptera)
How did bats evolve?
interdigital webbing hypothesis: the ancestral bat exhibited interdigital webbing prior to powered flight ability
Powered flight may have evolved multiple times within the chiroptera- convergence
Yangochiroptera, Pteropodidae, and Rhinolophoidea evolved parallel trajectories from this common ancestor.
What was the role of flight and active
echolocation during evolution?
Prey detection and identification in the dark
allows them to have different foraging habits- open spaces or dense vegetation
flight an ecolocation inextrcably linked
What are bat wing characteristics?
strong but fine and delicate bones
reduction of ulna and carpals (maneuverability)
fusion of cranial bones (bird-like)
sesamoids- bone embedded in tendon
Bat life cycle
Spring born
summer they brood and grow
fall reproduce
winter hibernate
How do bats adjust their foraging strategies to urban environments?
Urban bats more exploratory: visit more sites per hour and switch foraging sites
diversified their diet
many bats roost in countryside but commute to forage in urban environments
special bat diets:
fish
frog
mammals (small rodents)
blood licking
What is active echolocation used for?
Are bats the only ones to use it?
Orientation and Prey detection
No, flying foxes
cave swiftlets
oilbirds
dolphins and whales
How do birds echolocate?
click-type Biosonar signals
syrinx, the vocal organ specific to birds and found near to where the trachea forks into the lungs.
Birds use their syringes to produce broadband click-type biosonar signals that allow them to nest in dark caves and tunnels
echolocation found in at least 16 species- evolved convergently
Types of echolocation
CF-FM signals - hunt in dense vegetation-single frequency, then dip
FM signals- hunts in open space- extensive range of frequencies
What can be recognized from echolocation?
Distance: time btwn call and echo Velocity Flutter information Size of prey Horizontal localization vertical localization surface structure - (temporal and spectral structure of echoes)
How does echolocation influence foraging behavior
and habitat use?
Bats in open and edge spaces - aerial hawking - detect localize prey by evaluating pulse-echo trains , prey echo is unmasked
Bats in narrow space - solve pattern recognition task - flutter detecting strategy and/or active gleaning and/or passive gleaning strategy
How are bat ears different?
typical mammalian ear with some specializations
CF-FM (bats dense vegetation) high frequency slightly above end of spiral
How can moths respond to foraging pressure by bats? What is
the ‘evolutionary arms race’ between bats and moths?
Insects can: Avoidance behaviors: fly away, diving, turning, zigzag Produce ultrasonic clicks Isolate from spaces where bats live
Bats in response
Shift frequency range
reduce intensity of emitted sound
cease echolocation and use passive hearing
What are the ampullae of Lorenzini?
electroreceptor organs
Which animals are capable of electro sensing?
Some amphibia
osteichthyes
chrondrichthyes
agnatha
bees are also capable of electroreception
mammals like platypus, echidna, dolphins
How do bees electro recept?
detect by deflections of many tiny filiform hairs on head and body
bees are positively charges, flowers negatively
How do mammals electro-recept?
They have specialized mucus gland electroreceptors (monotremes: platypus and echidna)
Dolphins have vibrissal crypts on the rostrum
What are types of electroreceptors?
ampullae of Lorenzini
modified mucus electroreceptors
modified vibrissal crypt electroreceptors
How do freshwater sawfish and shovelnose rays detect
natural electric fields?
in aquatic environments organisms emit weak dipole electric fields
They use ampulla of lorenzini
The elongation of the sawfish’s rostrum clearly expanded their electroreceptive search area into the water column and enables them to target free-swimming prey.
How are electric fields used?
Finding prey
mates
environmental navigation
How are natural electric fields created?
muscle potential of animals
potentials from wounded animals
potentials from body openings
potentials from gills of aquatic animals
