Browse to EBI's ClustalW page generate a multiple alignment online:

1. Get some sequences of Hemoglobin beta chain. Download protein sequences of different organisms. Make sure you have sequences from some distantly related organisms as well as some closely related. Include sequences from mammals, fishes and birds. You can select sequences either from UniProt of your own choice or simply use the sequences contained in this multiple fasta file.
2. Go to EBI's ClustalW web page and align the sequences.
3. Use JalView to get a graphical overview of the alignment. The program allows you to choose between different colour themes. Histograms let you quickly identify regions of high homology.

Examine the alignments for patterns of sequence similarity that let you group some sequences together as distinguished from one or more other sequence(s):

1. Which mammal is most closely related to humans? Which mammal is most distantly related to humans?
2. Which are more closely related to mammals: fish or birds?

ClustalW returns the guide tree which was used for the progressive alignment as one of the output files. This tree can be visualized on the web page as phylogram or cladogram. A phylogram is a branching diagram (tree) assumed to be an estimate of a phylogeny, branch lengths are proportional to the amount of inferred evolutionary change. A cladogram is a branching diagram (tree) assumed to be an estimate of a phylogeny where the branches are of equal length, thus cladograms show common ancestry, but do not indicate the amount of evolutionary "time" separating taxa.

1. How do the trees correspond to the observations you made in the exercise above?