Bury me alive, and I won’t die. Who am I?

Slice me in half, I’ll have a twin.

I’ll mix things up, using my skin.

Bury me alive, and I won’t die.

I know when it’s light, but have no eyes.

Who am I?

You are

A worm

Slice me in half, I’ll have a twin.

If you cut one in half it looks like you have two worms.

I’ll mix things up, using my skin.

In travelling through the soil, they churn it as they go (due to their slightly "ribbed" bodies).

Bury me alive, and I won’t die.

They live underground.

I know when it’s light, but have no eyes.

Worms have light-sensitive cells which help them tell the difference between light and dark.

• I think that the second part of the clue was based on a misconception that makes it stronger than the reasoning in your answer (but yours is correct). – Guy G Jul 6 '18 at 9:12
• iirc, they die after a short time of decapitation tho – hanshenrik Jul 9 '18 at 8:35
• Cutting a worm in half does not create two worms. It simply looks like you have two worms (the reasoning behind my answer). – ck459 Jul 9 '18 at 8:54

Could it be...

A seed / plant

Slice me in half, I’ll have a twin.

Most seeds come in two 'halves', and can easily be split apart down that line. (pretty sure there is some species of seeds that can live when cut in two.)

I’ll mix things up, using my skin.

Weird things happen inside that seed as it turns into a plant... On the outside, it starts to grow roots, and interact with the soil.

Bury me alive, and I won’t die.

You can bury a seed in the ground and it lives perfectly well.

I know when it’s light, but have no eyes.

They can't see, being a plant, but it can definitely tell when the sun is out (certain flowers only bloom at certain times of the day, a plant will grow in the direction of light, etc.)

• This was my first thought, but ck459's answer fits the skin part much better. – arp Jul 4 '18 at 15:16
• Interesting unexpected answer. – iBug Jul 5 '18 at 6:59
• I think the cut in half thing is a distraction in the puzzle, many seeds die if you cut them in half, and a lot of (most I think!) worms die too if you cut them in half. – Prof. Falken supports Monica Jul 6 '18 at 15:21
• @Prof.Falken I'm still unsure whether we are supposed to assume that "cut in half" means that it can live. The riddle doesn't say it HAS to live, just that it will have two parts that look identical. – iiiidk Jul 6 '18 at 18:04
• @iiiidk, thanks for that, a new thought. – Prof. Falken supports Monica Jul 6 '18 at 18:47

You are

A potato

Slice me in half, I’ll have a twin.

Potatoes can be cut in half, and each half can grow a new plant

I’ll mix things up, using my skin.

Many recipes for filled potato skins

Bury me alive, and I won’t die.

Bury a potato, and it will grow

I know when it’s light, but have no eyes.

Potatoes turn green in the light.

• exactly what I was thinking – Nitin Sawant Jul 5 '18 at 9:23
• Potatoes have eyes. – Stephen Paulger Jul 5 '18 at 10:06
• ^ 48 upvotes to that comment!! – Manoj Kumar Jul 9 '18 at 10:00

You are

an electricity cable

Slice me in half, I’ll have a twin.

some electricity cables contain two wires

I’ll mix things up, using my skin.

if you want to join two cables, you remove their skin

Bury me alive, and I won’t die.

A live cable is a cable with electricity flowing in it. If it is underground it will still let electricity flow

I know when it’s light, but have no eyes.

electricity is used for making light

• Interesting thought! – xxx--- Jul 5 '18 at 9:14
• But you're removing the "skin" to mix (splice) wires, you don't use the skin to make the splice... Interesting answer though! – Doktor J Jul 6 '18 at 18:48
• Just because the electricity makes light, why would the wire know when it's light? – Heimdall Jul 8 '18 at 10:24
• @Heimdall - The wire gets hot when the light's turned on. – J.R. Jul 8 '18 at 22:07
• @Heimdall it goes directly to lightbulb, of course it know where it is. Fun fact: in my language electricity is often called "light". – talex Jul 9 '18 at 4:17

You are

a sea star

Slice me in half, I’ll have a twin.

sea stars have the ability to regenerate

I’ll mix things up, using my skin.

mixing the sand using its skin??

Bury me alive, and I won’t die.

you can bury it on the sand and it won't die.

I know when it’s light, but have no eyes.

they can't really see but can sense light

• you can bury it on the sand and it won't die. Really? I supposed it needs water. – Sigur Jul 4 '18 at 16:36
• @Sigur It could be interpreted as the sand at the bottom of the ocean. – Tin Man Jul 5 '18 at 11:20
• @TinMan, ow, in this case, yes... lol – Sigur Jul 5 '18 at 12:42

It could be a

Cell

Slice me in half, I’ll have a twin.

Cells when split are 2

I’ll mix things up, using my skin.

Some cells when they move mix around substances around them with their membrane/wall

Bury me alive, and I won’t die.

If you bury a cell, it still lives

I know when it’s light, but have no eyes

Photo receptive cells

You are

Slice me in half, I’ll have a twin.

Planarians are known for their regeneration capabilities

I’ll mix things up, using my skin.

Bury me alive, and I won’t die.

Some species of Planaria are terrestrial and can be found digging in dirt.

I know when it’s light, but have no eyes.

Planaria have photoreceptors which can detect light.

You could be

Baker's yeast

Slice me in half, I’ll have a twin.

Yeast is a clump of bacteria that can be split pretty often

I’ll mix things up, using my skin.

The bacteria on the outside react with the surrounding sugar, produce CO2 and make the dough grow.

Bury me alive, and I won’t die.

You can bury it in dough just fine.

I know when it’s light, but have no eyes.

Yeast is sensitive to light and will die if exposed for too long.

• Yeast is not a bacterium but a fungus. But yes, a lump of yeast is a clump of single cell organisms. And it's that fungus that eats sugar and creates bubbles of CO$_2$ in the dough. – Heimdall Jul 8 '18 at 10:42

You are

A line.

Slice me in half, I'll have a twin.

If you slice a line in half, you will have two lines with equal lengths — it was never mentioned that it must be sliced into two arbitrary parts. Twins!

I'll mix things up, using my skin.

You can draw all kinds of shapes and pictures using lines.

Bury me alive, and I won't die.

Bury lines in colour, and it might even look more alive than what it was. (I assume that the lines are alive until they are rubbed out.)

I know when it's light, but I have no eyes.

Not too sure about this one, but possibly refers to the colour of the surface on which the lines have been drawn on — it could be light or dark.

Who am I?

A line is not a who, which is what I think degrades my answer. Nice riddle, though!

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