Notes 1/25 pages 185-87

Hall Textbook- Zoe Verma


Inferring Species Relationships

We Will Write a Custom Essay Specifically
For You For Only $13.90/page!

order now

·      Things like early development patterns
and body structure show scientists that evolution occurred

·      Today, scientists are able to compare
DNA and protein sequences to see how organisms are related

·      They use all the strategies mentioned
above to find the evolutionary relationships among species

Similarities in DNA

·      “Scientists infer that the species
inherited many of the same genes from a common ancestor”

·      Genes are made of DNA

·      Scientists compare how closely related
species are by comparing the nitrogen bases in the DNA, and the more similar
DNA sequences are, the similar the species are

·      Scientists can compare the order of
amino acids in proteins to see how close species are to each other

Combining Evidence

·      Evidence from DNA and proteins have confirmed
questions by analyzing fossils, embryos, and body structures

·      Sometimes scientists change their
hypothesis about similarities between species

Branching Trees

·      “A branching tree is a diagram that
shows how scientists think different groups of organisms are related”


How do New Species Form?

·      “A new species can form when a group
of individuals remains isolated from the rest of its species long enough to
evolve different traits”

·      Isolation happens when a species
becomes completely cut off from the rest of the species; this can happen
through separation by a river, a volcano, or a mountain range

·      The Kaibab and Abert’s squirrel live
in the same area, and belong to the same species, but they have somewhat
different characteristics

·      For example, the Kaibab has a black
stomach while the Abert’s has a white stomach

·      It is plausible that in the future,
the two squirrels will become so different that they will branch into two different


I'm Niki!

Would you like to get a custom essay? How about receiving a customized one?

Check it out