Herp Test 2

activity temp range

bound by lower and upper voluntary temps

How to classify orgs by body temp

Temp variation and stability; cold blooded cant maintain its own body temp, warm blooded can. We prefer ectoderm and endoderm for herps

Endoderm

Maintains elevated body temps bcs of metabolic heat; ecotherm can't do this

Poikilotherm

Internal temp varies widely

Homeotherm

Can maintain stable internal temp

critical thermal temps

max and min temps preventing escape

Homeotherm ex

Mammals, birds, deep sea fish

Poikilotherm exs

Most fish. Hummingbirds, amphibs, reptiles

Critical thermal temp

CT max and CT min temps preventing escape leading to physiological failure

mean activity temp

mean of all temps for an animal; Tb

preferred temp

temp selected by individuals in an ideal environment

set pt temp

Tset; range of temps or temp at which animals attempt to regulate Tb

Operative temps

Te; equilibirum temp for an animal; temp of animal if we took behaviors away and left it alone like an inanimate object

thermoregulator

can keep interntal temp Tb in a narrow range even when external temps vary, most reptiles

thermoconformer

adopts temp Tb of surrounding environment as its internal temp, most amphibians; conforming to the environment; organisms can switch btw the two depending on conditions

all phsiological processes are

temp dependent

two most obvious physiological processes

water loss and movement

toads may retreat and emerge depending on

sunlight and water loss

lizards can avoid retreating for longer bcs of

endodermy

most improtant phsyiological process regualted by temp is

oxygen cconsumption

amphibs can regulate temp through

heat exchange via radiation, convection, or conduction; radiate energy is like flame from stove or light from sun; conduction is why handle of pot is hot or snake lying on warm rock; convection is mvmt of hot air or hot water

factors that affect heat exchange

color, body size, body position

optimal temp

Topt; temp at which performance is maximized; can have more than one depending on the performance

performance breadth

B80; range of temps at which an organism can perform at or above 80% of maximum

specialists vs generalists

specialists have higher maximum performance but lower performance breadth; generalist can perform pretty well at a variety of temps but is an expert at none

at warmer temps, organism defense chaanges how

from fighting and making body bigger, standing gground to fleeing or biting

colder body temp means more acctive at

night

why are amphibs nocturnal

lower body temp; avoiding water loss; hot water also holds less oxygen;

how can amphibs thermoregulate

hibernation; changei n actiivty, heatsinks in water; evaporative cooling from water (sweat), some have waterproofing or spreading of mucuous over body, seasonal variation

some lizards can only thermoregulate well and mainntain stable temp when

sun comes out and they can use convection and conduction, etc

nocturnal reptiles are

thermoconformers; thermoregulators are the sun tanners

when its too cold, thermoregulators may become

thermoconformers; if conditons are stable, you don’t need to be a regulator either

how can sea turtles maintain warm demps in cold water

counter current heat exchange; warming of blood as it enters and leaves, venous vs arterial blood; oily blubber like skin for insulation

how can pythons increase and stabilize body temp after laying eggs

shivering or muscle contractions; this does cost oxygen and atp; trend reverses after eggs hatch.

what do herps do when env conditions don’t allow for homeostasis/ too hot or cold

go into dormancy; two difff modes; hibernation for cold, aestivation for anything else

terrestrial hibernation must occur

at sites below the frost line

cold tolerance

Reptiles can go colder bcs scaly skin prevents ice crystals from touching fluids. amphibs down to -1 to -2 C but they are freeze intolerant with some exceptions. wood frogs allow bodies to freeze while using glucose as antifreeze to protect cells. supercooling allows liquids to stay liquid below freezing pt bcs of solutes in body; can’t go below supercooling pt

how does freeze tolerance work

cryoprotectants from the liver distributed throughout body that minimize reduction of cell volume due to dehydration and extracellular ice crystals; only done in amphibs

epidermal cocoons

daily shedding of stratum corneum producing an impermeable layer around theselves to keep skin around them in respnose to hot dry conditions in amphibs; done underground

acquisition of energy is an interaction btw

biophysical env, resources, social systems, mating success, risks

assimilated energy can be devoted to

foraging or social interactions; specifically maintenance, growth, reproduction, storage, or mating opps

cost of endothermy

40 to 80 perc towards growth in ecotherms; 98% towards temp regulation and activity in endotherms

metabolism and temp in herps

metabolism scales with temp; reptiles have higher metabolic rate than amphibs bcs their bodies are more complex

behavior influences on metabolic rate- frog calls and body size

frogs calling at a high rate can be more costly than moving around; bigger you are, easier it is to move a set distance metabolically speaking, can be species specific though bcs of mvmt differences and predation styles

microhabitat

small areas that differ from larger surrounding area; use shifts with season and can even shift daily; can be species specific; allows many species to occur in same area

home range

area an individual occupies but does not defend from conspecificst

territory

area within home range that is defended, occasionally from other species too; can sometimes encompass entire home range

home range size varies based on

sexes, body size, pop density, resource density

home range can shift bcs of

prey mvmt, abiotic seasonal changes, routine resource depletion

why can home range increase in males over time

more males are dying over time bcs of predation and territorial battles; more variance in range size and competitive abilty in ind males vs females; females have inverse relationship btw home range size and density?

resource availability and home range size have

inverse relationship

territory

area w defendable resource of quality that is better than adjacent areas; good thermoregulatory area, access to resources, etc. ; these behaviors can expose you to predators and can lead to energy use; should be a fixed area that you are preventing intruders from invading; results in exclusive use of area by male

commonly defended resources for frogs

egg deposition sites, larval rearing sites like bromeliads, areas with lots of food

most mvmts occur within

home range

factors that influence mvmt

environment, abiotic factors, rainfall, population structure like density and demography, individual traits like sex, size, age

migrations tends to…

be directional, leaving a home range, defined beginning and end, energy stored up in preparation, related to overwintering or breeding events for turts and salamanders

dispersal

undirected long term mvmt to parts unknown; used by juveniles leaving their parents home range due to habitat instability, intraspecific competition, inbreeding depression

homing

ability of individual to return to original location

orientation

ability to return to relative position

migrations and honing sensory cues

olfactory, eyes, magneto reception, audotory system for maps, clocks, compass, and piliting

y axis orientation

orientation to escape route—typically toward edge habitat

some amphibs can only detect what wavelengths

full and short; can’t detect long in a meaningful way

some reptiles like sea turtles have magnetic reception bcs of

sensory adaptations due to enzymes in eyes that pick up magnetic waves—a theory for birds and possibly herps

t or f every amphib and reptile has social communications

t, but the amount varies

recognized communication

when organisms understand what is being said; visual, chemical, acoustic, tactile; predation can be a big pressure determining which to use

commmunication

cooperative transfer of info from signaler to receiver; requires signal and matched receptor; must change together to work

courtship in salamandridae (newts)

genial gland and tail waving to spread pheromone, unreceptive females are grasped until ready to mate

plethodotidae comm

mental and caudal glands, nasolabial grooves, eraser like on chin,

desmognathus courtship

females grasps tail, enlarged teeth and scratches by male to aid in absorption of pheromones

plethodon courtship 1

tail straddles and slapping on nose of to deliver pheromones using mental gland (eraser thing)

acoustic frog comm

thought that absence of light and use of buccal breathing led to vocal sacs; calls vary and form basis of sexual selection

frog call signals

advertisement (courtship, territorial, encounter), reciprocation call by females, release call from fellow male toads when amplexed by mistake, distress call

components of accoustic signals vary by

call and call rate, note and note rate, pulse and pulse rate, spectral frequency

cost of acoustic signals

when doing encounter call, you can’t do advertisement one, synchronous calls can increase volume and also can confuse predators- 1 of 20, aynchronous calls may give access to more females but higher risk of predation

species produce both

chucks and wines, females prefer the more complex call but does put them at risk of predation

visual comm

toe tapping and foot flapping

tactile comm

varies when in amplexus

turtle comm

mainly visual and chemical; head bobbing, butting , biting, rathke glands on bridge of shell, mental glands, some tactile signals like in Emydidae-a lot of LA turts; finger/claw waving in face of female

crocodylian comm

visual signals for short distance, acoustic for long like bellowing and juvenile grunts

lizard comm

visual signals, nocturnal have auditory, chemical signals from femoral galnds, colors, dewlap extension, head bobs, push ups, brightly colored males, colors display social info both to other males and females

rock paper scizzors

orange rock, blue scizzors, yellow paper blue cooperately beats yellow; yellow looks like females snakes mates from orange, orange beats blue

pheromones in lizards

femoral glands used to differentiate btw species, sexes and receptivity; tend to be seen in small individuals like scincidae and lacertidae; fossorial individuals

snake comm

chemical and tactile, cloacal glands pheromones for defense and trailing, used for defense, pursuing mates, migration; tactile for close range, reproductive stim like tail dance on female, male male wrestling; tail mvmt for warning, distraction

3 phases of tactile commm

tactile chase, tactile alignment, intromission and coitus; tail used to find cloaca for hemipenes, head rubs on females back as stimulation

mating systems and strateigies

polygamy sometimes, satellite males, sexual interference, sexual dimorphism and sexual selectionfa

mating systems factors

female and male mating capacity, operational sex ratio, density, breeding period, parental care which can influence male mate choice

polygamy types

polyandry females w more than one male partner; polygyny where males have many femalesma

mating success

number of mates acquired

fecundity

number of offspring produced

polygyny mating defense

female defense, resource dfense, leks, scramble ccompetition

polyandry

male defense and resoruce

monogamy

mate guarding and or assistance

male parental care is seen in

monogamy

amphibian mating systems determinants

frequency of breeding explosive or prolonged, internal or external fert as reptiles only have internal

salamander systems

breeding location, aquatic species have little time to establish and defend territory, terrestrial have prolonged breeding, all polygynous

salamander explosive

desposits of spermatophores can be form of competition, courtship in some, males may mimic females to trick other males; males aplex females

prolonged breeding slamanders

terrestrial and resource defense polygyny, males hvae territories than don’t overlap; females territory overlap w males

frog explosive

male-male or scramble comp; females stay for short time, seeen in water limitation; predators incr as hydroperiod increases

frog prolonged

resource defense polygyny, males defend territories in bullfrogs; centrolenid frogs, males guard eggs bcs he knows all the eggs are his, females amplex, or males do not guard eggs but aplex

frog exceptions

polyandry in some hyperoliid frogs where female deposits part of clutch with male but then finds another one; monogamy occurs in some Dentrobatid frogs where male and female defend territory bcs good breeding areas are rare, tadpoles are cannibalistic,