FOSSILS
Fossils combined with genetic evidence help explain this process.
Evolution by natural selection over long periods of time.
This pattern describes how humans, bat, and whales all have the same basic limb bones arranged similarly despite having different functions.
Shared anatomical pattern of tetrapod limbs
This gene controls limb development in vastly different animals.
The Hox Genes
True or False: Evolution means that individual organisms change during their lifetime to adapt to their environment.
False.
Early embryos of different animals often look similar because of this shared feature.
Shared genetic program for development.
Early tetrapod fossils reveal this transition from aquatic to land life.
Evolution from fish fins to limbs
The human arm, bat wing, and whale flipper are examples of this type of structure that reflects common ancestry.
Homologous structures.
Why was the discovery of the hox gene important?
Provides strong evidence for common ancestry.
True or False: Natural selection acts on traits that are controlled by genes and can be passed to offspring.
True.
These genes are active during embryonic development and shape body structure.
Hox genes.
Fossils discoveries support the idea that similar limb structures evolved from this type of ancestor.
Common aquatic ancestor.
The anatomical evidence that supports the idea that humans share ancestry with early tetrapods.
The similarity in limb bone structure between humans and other tetrapods.
Gene expression is described as,
When genes get turned on or off.
This type of evidence for evolution compares DNA across species.
Genetic Evidence
Similar embryo development across species provides evidence for this concept.
Common ancestry
The Tiktaalik is...
A unique fish with a wrist type bone that soon developed
A tetrapod is described as,
A four-limbed vertebrate.
This scientist helped show that similar genes guide development in very different animals.
Edward B. Lewis.
True or False:Similar limb structures in different animals suggests that they evolved independently with no shared ancestry.
False.
Explanation to why small genetic changes in embryos can lead to large differences in adult forms.
Regulation of development by genes such as Hox genes.
A transitional fossil is described as,
A fossil that resembles features from ancestors and its descendant group.
This explains why very different animals can have similar bone structures even if they live in different environments.
Evolution from a common ancestor.
This evidence supports evolution by showing that different species use the same developmental tools.
Shared Hox genes support the theory of evolution by common descent.
True or False: Evolution invents new genes for new structures.
False: Evolution doesn't invent new genes for new structures.
Embryology supports evolution by showing that different animals develop using this shared system.
Conserved developmental genetic tools.