|
|
Your skin wrinkles if you stay in the bathtub a long time because the outermost layer of skin (which consists of dead keratin) swells when it absorbs water. It is tightly attached to the skin below it, so it compensates for the increased area by wrinkling. This happens to the hands and feet because they have the thickest layer of dead keratin cells.
The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
A strange skin disease referred to as Morgellons has occurred in the southern United States and in California. Symptoms include slowly healing sores, joint pain, persistent fatigue, and a sensation of things crawling through the skin. Another symptom is strange-looking, threadlike extrusions coming out of the skin.
Medication errors are three times higher among children and infants than with adults.
About 3% of all pregnant women will give birth to twins, which is an increase in rate of nearly 60% since the early 1980s.
![Succession in the intertidal zone involves colonization and competition for limited space among spec](https://biology-forums.com/gallery/47/medium_33_17_02_12_6_53_46_2016316.jpeg)
![Variation in coat pattern in zebras. The patterns show progressively more black left to right and to](https://biology-forums.com/gallery/47/medium_27759_23_04_12_7_25_57.jpeg)