What do biologists say caused this change in location to take place?
2007-02-24 02:08:56 · 7 answers · asked by Fearless Fosdick 1 in Science & Mathematics ➔ Biology
This is not strictly the case. If you have a female dog or cat or pig, check out it's belly. The nipples are spread all along the belly. I think elephants have their mammary glands between their front legs.
In evolution, sometimes things just happen. If a species is likely to have many babies with each birth, there need to be lots of nipples. If they are more likely to have single or twin births, two is enough and they can migrate in either direction.
2007-02-24 04:02:02 · answer #1 · answered by Joan H 6 · 1⤊ 0⤋
Perhaps it's because our lower torso is further from the ground when we are standing upright than if we are bending over. Primates use their arms to hold their young and so having the mammary glands on their chest means the baby can be held more easily in place.
2007-02-24 02:19:44 · answer #2 · answered by davidbgreensmith 4 · 1⤊ 0⤋
The young of four-legged mammals feed from the ground. The young of upright animals are held in the arms where the breasts must accessible.
2007-02-24 02:34:24 · answer #3 · answered by Anonymous · 1⤊ 0⤋
I don't know what a "biologist" would say, but I would say that it has to do with the arm reach of upright walking animals. They carry their young with their arms, and it's just a more convient location to let the young feed while holding them.
2007-02-24 02:25:40 · answer #4 · answered by Texas Underdog 6 · 1⤊ 0⤋
The trunk and the torso are the same thing. The upper part is the chest, the lower part is the abdomen.
2016-05-24 05:38:17 · answer #5 · answered by Anonymous · 0⤊ 0⤋
closer to eye level for our viewing pleasure
2007-02-24 02:16:43 · answer #6 · answered by J C 2 · 0⤊ 1⤋
Balance.... and they look GREAT
2007-02-24 02:12:14 · answer #7 · answered by lfchockey97 2 · 0⤊ 0⤋