Social Media Sidebar

Announcement

Please sign up, comment on articles and bring your friends!

Current poll

PlanetTech is asking:

What do you think about our new web site?

Love it, indeed
Really good solution
Same as old one
The old one was better
This is a new option

Quote of the day

We are all now connected by the Internet, like neurons in a giant brain.

 

Stephen Hawking

 

DNA Studies Topple the Ladder of Complexity

RATE THIS! +35
Posted in Science on 31st Jan, 2014 12:01 AM by AlexMuller

Amoebas are puny, stupid blobs, so scientists were surprised to learn that they contain 200 times more DNA than Einstein did. Because amoebas are made of just one cell, researchers assumed they would be simpler than humans genetically. Amoebas date back farther in time than humans, and simplicity is considered an attribute of primitive beings.

 

It just didn’t make sense.

 
The idea of directionality in nature, a gradient from simple to complex, began with the Greeks, who called nature physis, meaning growth. That idea subtly extended from changes over an organism’s lifetime, to changes over evolutionary time after Charles Darwin argued that all animals descend from a single common ancestor. When his contemporaries drew evolutionary trees of life, they assumed increasing complexity. Worms originated early in animal evolution.
 
 Creatures with more complex structures originated later. Biologists tweaked evolutionary trees over the following century, but generally, simple organisms continued to precede the complex.
 
Take the textbook scenario on early animal evolution. It essentially goes as follows: Single-celled organisms gained the ability to adhere to and communicate with one another more than 600 million years ago, and from the resulting colonies, the first multicellular animals emerged.
 
Today’s sponges, sedentary animals on the sea floor with no guts, brains, or tissue layers, descend directly from some of these creatures. Some early animals then organized their cells into distinct tissue layers, and some of the cells formed nerve cells, muscle cells, and other types.
 
Later yet, some animals developed serially repeated segments that served as a platform for legs and claws in their descendants. Then an animal with a spinal column evolved, and then one with a column surrounded by bony vertebrae. A recent branch to split from the tree blossomed into humans.

Tags: natureanimalsevolutionDNAgeneticsgenomebiology

Read original article » Back to category

Comments

Author: Guest
Posted: 2014-01-31
+2
More DNA may not imply more complexity. Complexity comes from interactions between the genes and communication between specialised cells in multicellular organisms - amount of DNA or number of genes may not be sufficient to assess biological complexity
3 Replies
Author: Guest
Posted: 2014-01-31
+0
Another thing is that complexity at the molecular level is not always on the increase during the evolution. And, some more complex organisms, could be "simplified" during evolution. Reply
Author: Guest
Posted: 2014-01-31
+0
Yes, and they say that the environment selects whatever form handles the challenges at hand, be it simple, complex, or plain ugly. Reply
Reply
Author: Guest
Posted: 2014-01-31
+1
They are considering two concepts here: -a complex nervous system and muscles were lost in the sponges and -the sponges had the genetic capability for complex features but stayed simple. Both run counter to scenarios in which organisms evolve to be increasingly complex. Reply
Author: Guest
Posted: 2014-01-31
+0
People are quite interested in oddities of evolution. Site “Go Home Evolution, You’re Drunk,” features organisms with sub-optimal traits that have managed to survive just fine. Great fun! Reply


 

Recent headlines

  • Posted in Science on 2017-08-16 23:13:20
    There’s a lot of money up for grabs if you can land.....read more
    Posted in Medicine on 2017-08-16 18:10:10
    3D printing living tissues to form living structures..read more
    Posted in Medicine on 2017-08-16 18:07:30
    algorithm can spot depression based on your Instagram posts..read more
    Posted in Business on 2017-08-16 18:03:59
    Ethereum sets new transaction record, outperforming Bitcoin..read more
    Posted in Medicine on 2017-08-15 17:58:46
    'Fat but fit' still risk heart disease..read more
Posted in Business on 2013-10-10 01:33
China is working towards a manned lunar mission in about.....read more
Posted in Business on 2013-10-20 07:17
Spacex says China is their main competitor for commercial.....read more
Posted in Software on 2013-10-20 06:43
Pirate Bay Browser Clocks 1,000,000 Downloads..read more
Posted in Medicine on 2013-10-10 02:10
Google reportedly investing hundreds of millions into new.....read more
Posted in Medicine on 2013-10-14 03:13
Endothelial Cells Can Repair and Regenerate Organs,.....read more
Posted in Science on 01.01.2010
Spacex says China is their main competitor for commercial.....read more
Posted in Science on 01.01.2010
Staring at Your Phone Could Be Making You Short Sighted..read more
Posted in Science on 01.01.2010
Oculus Rift virtual reality headset coming to mobile, but.....read more
Posted in Science on 01.01.2010
China is working towards a manned lunar mission in about.....read more
Posted in Science on 01.01.2010
Delivering drugs via nanoparticles to target mitochondria..read more

Recent Blog Posts

  • Posted by AlexMuller
    Newly discovered biomarkers may lead to promising diagnostic.....read more
    Posted by AlexMuller
    Understanding cell segregation mechanisms which help prevent.....read more
    Posted by AlexMuller
    Unique features of individual brains captured..read more
    Posted by AlexMuller
    Lutein, found in leafy greens, may counter cognitive aging..read more
    Posted by AlexMuller
    New surgical strategy offers hope for repairing spinal injuries..read more

Login to your Account

Login to your PlanetTech Account here

Username:
Password:
Remember me
or

Create a New Account

You just need username and password

The following errors occured:
Username:
Email:
Password:
Verify password:
Remember me