Switches are not identified.
Single-pole switches are wired differently than 3-way.
Wire colors are not identified. Some boxes have red and black wires that carry power.
Add a comment and fill out details after studying image and reading information.
I am not there, so you can also add a comment and include in-focus photo of your switches that you posted on Flickr.
Following image shows single-pole switches, with typical black and white wires.
No bare copper ground wire is shown. Ground wires connect to green screw.
http://waterheatertimer.org/images/Single-pole-switches-in-4-g.jpgSo your new switch has 2 brass screws. No white wire connects to single-pole switch. One screw will have 1 black wire that goes to light fixture. The other screw will have 1 or 2 black wires that jumper or connect to the other switches as shown in image.
White wires are usually twisted together and covered with wire nut and pushed to back of box.
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