Linguistic Archaeology: climate induced gender ratio collapse?

First off some background data:

Indigenous Australian Individual Names

DJ                              UL                          NG                           OTHER
Kadjali (m)              Tulu (f)                 Mirawong (m)       Ditzi (f)
Windjedda (m)      Bulla (m)               Dingle (m)             Manbuk (m)
Badju (m)               Bul-bul (m)           Wungala (f)*         Numeuk (m)
Djarapa (m)           Ngulwun (f)*        Ngulwun (f)*         Kunduk (m)
Mattindji (m)         Bulya (f)                Weingu (f)             Mamru (m)
Muradji (m)            Ulna (f)                                            Mamanduru (f)
Kudjerri (f)             AL                                                           Nadba (m)
                                 Jalnuk (m)                                           Kinunjun (m)
                                 Jalna (f)                                                  Dunia (m)
                                 Dalmaru (m)                                        Iramaru (m)
                                 Jamalumpowa (m)                         Kuparunni (m)
                                 Ninual (f)                                            Mardinya (f)
                                 Wungala (f)*                                         Yama (f)
                                 OL                                                            Lobor (m)
                                 No Names?                                            Maran (m)
                                 IL                                                      Minyinderri (m)
                                 Lumberlili (m)                                            Yaba (m)
                                 Billarra (m)                                               Marlu (m)
                                 Bilemu (m)                                              Bema (m)
                                 Milajun (f)                                             Kumbob (m)
                                 EL                                                             Inetina (m)
                                 No Names?                                          Gumajun (f)
                                                                                                  Ikeiginni (f)
                                                                                                   Bemini (f)
(f/m) female/male     33m, 19f
*multi-cultural

Ul, Al groups exhibit 50/50 gender balance showing long healthy period pre-18ky.
The El phonetic is tied to first human settlements (sel: settlement, pele: high place/citadel). Il is a pre settlement migration group. So its before first human settlements (18ky). Likewise podj-podj are described as size of small children so indonesian hobbits (18ky).

Conclusions: some subgroups (il phonetic-pre settlement humans, dj-podj-podj indonesian hobbit subgroup) exhibit near extinction with populations reduced to one woman and many males. Assuming same timeframe for shortage of females in pre settlement human, as with Indonesian Hobbits, approximately 18,000BCE.

If this is the result of climate change, then future climate change may result in greatly skewed population ratios between males and females leading to social collapse and a die-back of populations. So future climate change could affect birth rates for females resulting in less females. This will be pronounced in third world nations resulting in social chaos.

Updated (12/12/2018): these people are emerging from a bad ice age. There has been high parts per million dust recorded in Lake Vostok ice cores around 20ky-18ky along with temperatures as low as negative five, with very low CO2 count in lake vostok ice cores. Perhaps a bad Asteroid hit? The polar glacier ice extended across north America and up from Antarctica across the southern ocean. Sea levels are one hundred and twenty metres lower than they are at this time and in the millennia to come they rapidly rise.