Module 4 Part 2 Flashcards
Whatdi todays biologists believe in the central propositions of evolution
- That all living things are descended form a common ancestor
- That all extant species can change and give rise to new species
Proailurus evolved into
the modern cat
What genus are all the bears
Ursus
Spectated bear is part of
Tremarctos
Giant panda is part of
Ailuropoda
What order are all the bears
Carnivora
How many families are in the order Carnivora
13 families
Traits of order Carnivora
Strong sharp claws
more than 4 toes/foot
Canine teeth
Every bear is omnivore except ___________
Giant Panda
Family of Bears
Urisdae
When did family urisdae occur
25 million years ago
What is the ancestor of Urisdae
Cephalogale
Next family member of family Urasus
Dawn Bear
Evidence to support the theory of evolution
- Artificial Selection
- Fossil and the Fossil Record
- Biological Design
- Biogeography
- Convergent evolution
Artificial Selection
Selective breeding of animals and plants (by humans) over 100-1000s of years
Difference between artificial selection and natural selection
Artificial Selection works much faster than natural selection
What does the fossil record show
Historical sequence of events
What did ancient whales look like
4 legged animals
Knee cap and toe bones
Sinonyx jiashanensis
- Primarily land animal
- Probably hunted/scavenged
- size of a wolf
- built for stamina and strength
Pakicetus inachus
- Primarily a land animal (swims occasionally.)
- Size of a wolf
- Characteristic features of the inner ear (found only in cetaceans) - large auditory bulla formed from only the ectotympanic bone
Ambulocetus
Similar to pakicetus but with flittered feet - better adapted for swimming (most likely moved better in the water than on land)
Rodhocentus
- paddling, reduced hind legs; neck
- vertebrae shorter (less flexible neck), an adaptation for swimming
- ear region more specialized for underwater hearing
Durodon and Basilosaurus
- Vestigial hand limbs
- propelled by sturdy front flippers and long flexible body/tail
Evolution of whales
Sinonyx - pakicetus - Ambulocetus - Rodhocetus
Ancestor of all living horses, donkeys and zebras
Hyracotherium
Evolution of Hyracotherium
Equus
What fused as horses are evolving
Toes
Advantages of reduced number of toes
Development of hoof
Fast runner
What are horses teeth modified for
Grazing
Larger and more enamel (because diet changed from soft leaves to grass)
What is the earliest known bird
Archaeopteryx
What is the oldest feathered animal in the fossil record
Archaeopteryx
Skeleton of Archaeopteryx
- long bony tail
- ribs are free (not fused as in birds)
- hand bones are not fused (birds have claws)
- teeth
Features of a reptile
Bird features of Archaeopteryx
Wings
Feathers
A wish bone
What was the transition of Archaeopteryx
Transition from reptile to bird
Biological Design
Comparing Anatomy
Morphologically similar species suggest relationship
Ancestor of all dog like looking creatures
Canine
Only _________ features are used to infer evolutionary relationships
Homologous
Homologous Characters
Similar Ancestry
Analagous creatures
Similar Function
Homoplaisious Creatures
Similar Appearance
Example of analogous features
Dragonfly wings and Bat wings
Both used for flight
All characters are not ________ exclusive
Mutually
What kind if species are Thylacosmilus and Smildon
Analagous and Homoplasious
Homologous characters
Derived from a common ancestor
Vestigial Characters
Structures with no apparent function
Examples of vestigial structures in humans
Tail bone and appendix
Vestigial structures in snakes
No limbs
Comparative Embryology
Commonality of early stages, specifically in blastula and zygote
Example of common embryology
Pharyngeal slits in vertebrates
Gills in fish
Ears and throats in humans
Molecular Homologies
Similarities in DNA sequences
Biogeography
Geographical distribution of Species
Alfred Russel Wallace is the father of ___________
Geogrpahy
Convergent evolution
Suggests adaptation to the environment
Why do penguins and polar bears do not co exist
Because of Biogeography
Example of Convergent Evolution
Spiny Anteater and giant ant eater
Mole
Mouse
Squirrel
Natural Selection
Appears to have favoured parallel evolutionary adaptations in similar environments
Example of Natural Selection
Succulent plants
North American cactus
Clear, watery sap
Euphorbia Cactus
Milky, sticky snap
Relationship between North American cactus and Euphorbia
Distantly related
But have independently converged on a very similar body form
Microevolution
Changes in populations
(Continually happening)
Macroevolution
Formation of new species
(Small changes)
What is an adaptation
A bilogical adaptation is an anatomical structure, physiological process or behavioural trait of an organism that have evolved over a period of time by the process of natural selection
Phenotype
An individuals observable characteristics or traits
Phenotypic Variation
May be environmental or genetic in origin
Polymorphism
Different forms within a speice
Mutations are a reason for this
Why are Galapagos flamingos orange/pink in colour
They eat mccrocrustanceans (environmental)
Non genetic variation
Variation induced by environment only
Summer morph and Spring Morph
Are genetically identical at the loci for colouration. Colour changes due to seasonal differences in
Changes colour depending on season
Genetic variation
Genes control the colour
Example of inheritable variation
Postman Butterfly
Colouration of jaguar
Population
A group of individuals belonging to the same species who occupy a particular geographic region and potentially interbreed with each other
natural selection only acts on ___________
phenotypes
Crptic colouration
many animals blend in with their surroundings (type of camouflage)
Mimicry
Species resembling other species
Inanimate
Showing no sign of life; lifeless
Reproductive success influences ____________
Frequency
natural selection acts on _____________
Phenotypes
Natural selection is the differential reproduction of ______________
Genotypes
Natural selection indirectly accts on the ___________ and _________ frequency
Genotype and Allele
________ defend themselves by mimicking a snake
Hawk moth Caterpillars
Robber fly
Mimic as their prey - goes to the bee nest and blends in with all the others and then catches prey
Batesian Mimicry
Mimics the prey for their advantage
Red milk snake and Coral snake is an example of
Batesian Mimicry
Red milk snake - Non venomous
Coral snake - poisonous
Viceroy butterfly and Monarch Butterfly
Not BATESIAN
Vicoroy is more unpalatable than the monarch
Mullerian mimicry
Mullein mimicry
Ecologically sympatric pairs new distasteful, and have warning colourations
Industrial Mechanism
A phenomenon that affected over 70 species of moths in England
First Hypothesis of black moths
Blackness in moths caused directly by pollutants derived from smoke and industrial process, acting to alter the metabolism of the insects (RefuteD)
Beak sizes in Galapagos finches
Dry conditions produce large seeds and may result in larger beaks in succeeding generations due to natural selection
Beak length is genetically determined _____________
Inherited Characteristic
Sexual Cannibalism
Not Natural Selection
Only occurs in a few of the 180+ species of mantids
Also occurs in some species of spider, scorpion, crickets and beetles
Mantid Reproduction
Male dies after fucking
Provides a high energy source - egg development faster
Benefits of sacrifice in mantid sexual cannibalism
- As mates only once: Strong selection pressure to succeed
- Prolonged copulation while being eaten
- Prevents female from mating another male
Sexual Selection
Diversity in appearance between sexes (In sexually reproducing species)
Sexual dimorphism
Phenotypic differences between males and females
Traits
Secondary Sexual Characteristics
Two types of Sexual Selection
Intrasexual selection
Intersexual selection
Intrasexual selection
Between members of the same sex
Direct competition (e.g. physical combat)
Example of intrasexual selection
Male fiddler crabs use large claw to defend burrow in which a female lives
Intersexual selection
Between members of the opposite sex
Female choice
Example of Intersexual Selection
Bulwers pheasant
Temminck’s Tragopan
Indian peacock is an example of _____________
Intersexual Selection
Indian Peacock Males
Long and Brightly coloured tail feathers
Fan out during mating behaviour
Indian peacock females
Choose a mate based on certain traits (appearance, behaviour)
African Long tailed widowbird is an example of
Intersexual selection
Microevolution
Changes in allele frequencies between populations
Macroevolution
Formation of new species
Anageneis
Single species transformed into a new species over the course of many generations
Cladogenesis
Division of a species into 2 species
Only one that promotes biological diversity by increasing the number of species
Speciation
The process leading to the formation of new species
It is also the source of biological diversity
Allopatric Speciation
- Splitting of a population into 2 geographically operated populations
Separated by slow geological events - No gene flow between the isolated populations . No interbreeding
__________ isolation can promote allopatric speciation
Geographical
Allopatric speciation is what kinda genesis
Cladogenesis
Examples of Allopatric Speciation
Porkfish
Antelope Squirrels
