Wikipedia:Reference desk/Archives/Science/2017 May 26

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May 26[edit]

Mammals that sexually mature later than humans?[edit]

What mammals reach sexual maturity later than human beings? I'm counting both the ability to sire/bear offspring and also having reached more or less adult size.Naraht (talk) 02:03, 26 May 2017 (UTC)[reply]

The elephant, for one. ←Baseball Bugs What's up, Doc? carrots→ 02:51, 26 May 2017 (UTC)[reply]
Great White Sharks may be the latest, possibly as late as 26ish. --Jayron32 02:54, 26 May 2017 (UTC)[reply]
Except they're not mammals. But if that's the latest reproductive age of any creature, that puts a boundary around it. ←Baseball Bugs What's up, Doc? carrots→ 03:00, 26 May 2017 (UTC)[reply]
I don't think elephants is the correct answer. The elephant article does not mention when they achieve sexual maturity but mentions musth, which is not the same thing. Unfortunately I am at work and our connection is very slow so I can view Google results and Wikipedia but not much else. So Google provided the following results when I put in Mammals that sexually mature later than humans and that seems to indicate that humans are the latest. The partial result for the Quora site looks interesting. Then using Google to ask Sexual maturity elephants gives interesting results with this looking good. But exactly CambridgeBayWeather, Uqaqtuq (talk), Sunasuttuq 07:32, 26 May 2017 (UTC)[reply]
Actually, the article on elephants says sexual maturity is at about 9 years for a female, and 14-15 years for a male (several of the larger mammals have a similar difference between the two genders). That does not mean that a 15 year old male elephant would get a chance to mate, as it is competitive and the older, stronger males would dominate. That would imply that male elephants reach sexual maturity later than male humans - but not the females. Wymspen (talk) 11:48, 26 May 2017 (UTC)[reply]
I'm surprised that I missed that when I looked earlier. CambridgeBayWeather, Uqaqtuq (talk), Sunasuttuq 12:24, 26 May 2017 (UTC)[reply]
Nine-year-old male elephants have been known to mate if all the big males have been killed by poachers. Abductive (reasoning) 17:46, 28 May 2017 (UTC)[reply]
Are they less interested in almost menopausal elephants when they start to like girls just like humans? Sagittarian Milky Way (talk) 19:21, 28 May 2017 (UTC)[reply]
It seems that female elephants have lifelong fertility http://www.abc.net.au/science/articles/2013/10/28/3874904.htm --Digrpat (talk) 11:58, 29 May 2017 (UTC)[reply]

Exocrine system + endocrine system =?[edit]

What is the title name for endocrine system + exocrine system? In another language that my friend speaks they are called "secretion system" but in English the term secretion system is different and it is about proteins in Gram-negative bacteria. 93.126.88.30 (talk) 08:08, 26 May 2017 (UTC)[reply]

I believe the term glands encompasses both of those and also excludes other systems. --Jayron32 10:52, 26 May 2017 (UTC)[reply]
You can call it the glandular system, glandular being the adjective from gland. Wymspen (talk) 15:38, 26 May 2017 (UTC)[reply]

How does a creature adapt to city life?[edit]

What are the characteristics that a creature must have to live in the city? I presume size is important. Anything too big can easily be spotted by humans. The city has cement, asphalt, and concrete, not soil. I think some plants can slide in among the cracks of sidewalk. There may be parks, separated by tall buildings and desert-like cement floors. And fast-moving objects on wheels with humans inside roam the streets with big, shiny, blinding lights. Then, there are bright lights right next to the moon, so bright that they block out the stars. How do rats survive in the city? What other kinds of creatures can adapt to city life or farm life or face extinction because of habitat loss? 140.254.70.33 (talk) 18:59, 26 May 2017 (UTC)[reply]

One obvious example is the Rock Dove, which finds the sides and roofs of tall human buildings just as habitable as the cliffs and caves of its wild habitats.
(But whatever birds lived in the trees that were growing there before the city was built, might be out of luck.) ApLundell (talk) 19:05, 26 May 2017 (UTC)[reply]
Rock doves of course would be the common pigeon. The infrequent pure white variety looks very dovey. Sagittarian Milky Way (talk) 07:31, 27 May 2017 (UTC)[reply]
Habitat loss is not really about cities, e.g. in the USA our city cores all combined are still tiny compared to the vast expanses in between them. Habitat loss is mostly due to agriculture and deforestation with suburban sprawl playing a much more minor role. Animals that do well living around humans are called synanthropes. We have articles on urban forestry and urban wildlife that describe what sorts of species live around our cities, and you can look in to each of them to see what traits they share in common. Our article on rats explains a lot about how they do so well in some human settlements. Other common urban/suburban animals of North American include squirrels, mice, ground hogs, deer, flies, snails, slugs, ants, mosquito, sparrows, cardinals, blue jays, mourning doves, robins, anoles, geckos, skinks, frogs, etc etc. Tons of stuff lives all around us. See also urban ecology for further reading and references. SemanticMantis (talk) 19:13, 26 May 2017 (UTC)[reply]
By my personal observations, Urban foxes are persistent and common in UK towns and cities – driving home through Gosport last week I saw four or five, and had to slow down and flash my headlights at one before it would deign to vacate the carriageway. In the same town's pedestrianised high street, my friend (who lives there) was walking home late one night eating a bag of chips when a fox stopped in front of him, clearly soliciting a handout. When he paused, it walked up to him and tugged gently at his trouser leg, whereupon it was rewarded.
Badgers are also not uncommon in the area (which includes the cluefully named Fort Brockhurst), though they are somewhat shyer and are most often seen crossing cycle paths. (The same friend once cycled into one and broke his wrist – the badger was doubtless unscathed.) {The poster formerly known as 87.81.230.195} 90.200.129.108 (talk) 01:21, 27 May 2017 (UTC)[reply]
While some areas in big cities may give the famous impression "the city never sleeps" most areas are in fact almost completely free of human activity during night hours. Animals instinctively use these hours to wander from one green or hiding zone to another. In fact most animals seem to have much better natural planning and mapping capabilities regarding their living area than humans. They know when and where to move savely and unnoticed. --Kharon (talk) 04:16, 27 May 2017 (UTC)[reply]
Animals adapted for cliff-dwelling do well in cities. Animals adapted to forest edge and open woodland habitats do well in city parks. Abductive (reasoning) 17:48, 28 May 2017 (UTC)[reply]