Phylogeny and Evolution

By: Bernice Onuoha Kelechi Okereke

Edima Akpan Will Zepeda-Campos

Phylogeny is basically the study of how closely

related organisms are to one another through what derived traits they shared

The study of phylogeny is important so we can trace back how us humans, for example, evolved from a common ancestor and what common derived traits we shared with other organisms

We have constructed tree phylogenies for candy, mammals, human migration, and viruses

An Introduction to Evolution/Phylogeny

Techniques and Vocabulary Node- the point of common ancestry between two or more species

Clade- consists of a single organism and all of its descendents.

Synapomorphy- a shared derived character that evolved exclusively

Out-group- an organism that is closely related to the rest of the group but has the least common trait

Convergence – when a similar trait evolves more than once in different organisms

Polytomy- where more than two branches are branching off from the base of the tree diagram

Distance Method (Neighbor Joining)- the “quick and dirty” method used to determine how closely related organisms are to one another by using the number of changes that occurred between two organisms

Maximum Parsimony- technique used to make phylogenies using parsimony, assumes the simplest explanation is the correct explanation

Bootstrapping- a technique used to make tree diagrams in order for them to be read more accurately

Hershey’s Dove Kit Kat

M&MsTwix

Snickers

Baby Ruth

starburstGreater than230 calories

Wafer/cookie

More than 230 calories,Gain caramel

Gained nut and nougatLoss of pieces and wafer

Loss offruitinessCandy

pieces

?

Star burstHershey’s

Dove Kit Kat

M&MsTwix

Snickers

Baby Ruth

chicken

Echidna

kangaroo

wolf cat

human

monkeyporcupine

rabbit

Hedge hog

Open eye socket

hair

quills

viviparity

placenta

Distinctcanines

quillsClosed eye sockets

Distinctcanines

quills

Grindingteeth

Ever-growingincisors

Bootstrapping tells the confidence (%) of the node and if it can be trusted

Based on this phylogeny, Africa is the origin of humans because of its prevalence among the different nodes. Also it can be traced back the farthest

Made by mitochondrial sequence in DNA of different human populations

Migration of human population This map shows

the migration of the human population starting with the origin in Africa.

The tree shows:• The different strain of the Swine Flu virus around the world

• That Swine Flu spread quickly and evolves rapidly

Battle in evolution:

•Humans and viruses have coexisted for millions of years.

•Humans fight viruses using vaccines which are weakened forms of the virus, which helps the immune system recognize the virus to produce antibodies

•Viruses change in order to infect

conclusion

Phylogenies are useful because it helps us to better understand how different organisms are related.

The projects that we did helped us to better understand how to make phylogenies